


Bonding

by Aifrit



Category: Final Fantasy, Final Fantasy XIII, Final Fantasy XIII Series
Genre: Breathplay, D/s, Dominant, F/F, Family, Farroncest - Freeform, Femslash, Headcanon, Incest, Masturbation, Morning Sex, Plot What Plot/Porn Without Plot, Romance, Submissive, Yuri
Language: English
Status: Completed
Published: 2013-03-27
Updated: 2015-05-18
Packaged: 2017-12-06 16:46:45
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 4
Words: 19,532
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/737897
Author URL: https://archiveofourown.org/users/Aifrit/pseuds/Aifrit
Summary: <blockquote class="userstuff">
              <p>Lightning finally has a day off to spend time with her sister, Serah. Lightning knows Serah - she isn't as innocent as everyone thinks she is - yet the soldier still can't resist her. Farroncest. Written for FFXIII Kink Meme.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> Title: Bonding  
> Pairing: Farroncest (Lightning/Serah)  
> Rating: M for sisterly incest and some language  
> Words: 5,384  
> Song Inspiration: “Ecstasy” - Tinashe  
> Prompt Request: “Lightning may dominate Serah in bed, but sex-devious Serah is the one who really pulls the strings in their relationship. Orrrrr simply, Lightning can't resist Serah, and Serah ALWAYS gets what she wants from big sis.”  
> Disclaimer: I do not own these characters nor am I making any profit from them. They belong to their right owners.
> 
> A/N: This story was written to fulfill a prompt on the FFXIII Kink Meme. It was originally supposed to be shorter but kind of evolved into this long two-shot. Oh well. I haven’t written fanfiction in a very long time so I hope this isn’t bad. Reviews and all that would be welcome. If I get enough of them, I’ll know that people are interested in seeing part two whenever I finish it. Enjoy!

Cold. She flinched. What was that? She cracked her eyes open, wary of the sunlight that broke into the room. She scanned the night stand next to the bed. Navy walls. Her gunblade against the wall in the corner. Uniform lying haphazardly across the floor. Oh. It was her room. She barely even remembered getting home last night after work. 

The yawn that escaped her morphed into a sigh. She made to stretch out an arm but recoiled upon feeling a painful tug. Had she _ever_ been this sore? She’d have to remember to stretch later. Before she moved, she felt the cold again. She flinched once more. It took her a second to realize what it was. Fingers. Chilled fingers, right on the exposed skin of her back, between the tank top bunched around her waist and the shorts low on her hips. “Serah?”

She heard a chuckle from behind her. “Morning, Light. Did you sleep well?”

Her voice was a lazy, hoarse drawl when she spoke. “Mmmm…decently enough.” She must have; her memory of getting into bed last night was hazy at best. She rolled over and faced her sister, aquamarine eyes meeting crystal blue.

“I figured. You passed out the second you hit the bed.” Serah moved a strand of strawberry-blond hair from Lightning’s face. “You looked so tired last night. I even had to help you out of your uniform.” She paused, locking eyes with her older sister. “I wish you didn’t work so hard.”

“It’s all for you, Serah.” Lightning caressed her sister’s cheek with the knuckles of her hand. “I’ll work forever as long as I know you have whatever you want and need.” It was the same response she gave every time Serah showed concern for her well-being. Regardless, it was true. Serah would be starting college soon so every bit of income was more than welcome. “Besides, it’s not that I don’t like the work. It’s tiring at times, but it keeps me active.”

The corner of Serah’s mouth rose. “I noticed.” She brushed fingertips over the outline of Lightning’s abs. “You always were one to stick to physical activities.”

“It’s Guardian Corps. I have to stay in shape.” Being in the military was not an easy job, even in a tranquil seaside city like Bodhum. Soldiers were required to stay in top form and prepared for any disaster.

Serah sat up on an elbow. “Aren’t you sore though? You’ve been gone for almost two days straight and I’m sure you didn’t get much rest.”

“No, I didn’t. I…am pretty sore. I’ll be fine though.”

“I hate when you’re gone that long. I missed you. A lot.”

“I’m sorry. I missed you too.” 

Ever since Lightning joined Guardian Corps., she’d been working herself to death in order to provide for the both of them as well as keep Serah in school. Some days, she never even had the opportunity to return home. The two barely spent time together like they used to and Lightning loathed it. But she promised herself to take more days off to spend time with her younger sister even if that meant she’d make up for it later on. Today was one of those days.

Lightning sat up and attempted to stretch again. She winced feeling her locked joints and muscles sear in pain.

“Hey don’t strain yourself.” Serah crawled behind Lightning and rested on her knees. “Relax, okay, sis?”

Lightning felt small hands on her back and shivered. Light touches over thin fabric morphed into pressing, kneading, and rolling. Lightning sighed, leaned her head forward, and closed her eyes. The hands traveled to her shoulders, upper back, mid-back, and then lower back. They cared for the back of her neck and even her sides, making her flinch. Serah knew every spot, every usual knot and ache, and kneaded them all into oblivion. It was only when Serah stopped that she snapped her head up.

Serah wrapped her slender arms around Lightning’s taut midsection. “How’d that feel?” 

She murmured. “G-Great. Thank you.”

Serah trailed her lips up the back of Lightning’s neck as she spoke, “Anything for you, big sis.” She gave her sister one last squeeze before hopping off the bed.

It was then that Lightning noticed that the smaller strawberry-blond girl had slept in one of Lightning’s T-shirts with just underwear covered in cartoon kittens to accompany it. Even waking up with hair mussed and wild, and wearing close to nothing, she still looked…adorable.

The smaller girl shifted her weight to one foot and rubbed her eye with the back of her hand. She yawned. “Why don’t you go take a shower and I’ll start on breakfast?” 

Lightning nodded. It would be nice to rid herself of the grime she accumulated from work and finally get a proper shower. The showers of the Guardian Corps barracks were mediocre at best – all they did was get the job done. She ambled to the bathroom while Serah walked off to the kitchen. Leaving the bathroom door at a crack, she turned the water on, then undressed. She hadn’t gotten in the shower yet and she could already feel the relief. Steam filled the bathroom and the sound of the water tapping away in the shower relaxed her. She slid back the glass of the shower door and stepped in, relieved by the initial sting of hot water. It was lovely. It’d been a couple days since she was able to use her own shower and she planned on enjoying every minute of it. Leaning back against the wall, the droplets pelted her face and her mind began to race.

She felt terrible about not being able to spend much time with her sister. Serah was a wonderful straight-A student who was never one to get into trouble. She deserved to have someone there with her, to do things with her whether it was going to the mall or just lounging around watching a movie. Lightning’s heart panged with guilt; she felt like a terrible sister. As a result of her strenuous job, Serah began to make a whole new set of friends outside of school. NOEL..err- NORA? Was that what they called themselves? Regardless, the thought of them made her head ache. They were a no good bunch of ruffians who only made Guardian Corps’s job harder than it needed to be. The military didn’t need an independent vigilante group running around taking care of their assignments. They were civilians eliminating stray monsters and dangerous wildlife in the area. The point of Guardian Corps was to _protect_ the civilians, not prevent them from doing Guardian Corps.' jobs.

And NORA’s leader – Snow. Lightning clenched her teeth. She wasn’t sure how someone like _him_ could ever lead such a group. He was charismatic, sure, but not entirely the brightest chocobo in the herd. Serah had been hanging around him a lot in the past few weeks. Lightning despised it – despised _him_. Her sister called her out on it once or twice, saying that “green was such a nice color on her”, jokingly of course. But was that the problem? Was Lightning just….jealous?

_Serah is mine._

Lightning opened her eyes, not recalling that she’d closed them in the first place. She tensed when she noticed movement beyond the glass door.

Serah’s voice rang through the bathroom. “Light? Are you okay? You’ve been in here a while.”

The soldier could see Serah’s muddled form through the glass. A blob of pink and cream shifted closer to the door - she was coming in.

The glass door opened. Lightning remained where she was – leaning against the wall, head tilted back on the marble tile. The water continued to pelt her face and her hair. She didn’t care, only paying attention to the lean, naked figure stepping into the shower next to her.

Serah stepped into the shower right under the water where her sister stood. She smiled and then threw her arms around Lightning’s neck. “I know I told you already, but I… _really-_ ” She trailed her lips up Lightning’s neck, closer, caressed the shell of her ear. “ _-really_ missed you.” One hand ghosted in the valley of Lightning’s breasts, running lower, lower…lower. _“Claire.”_

Lightning chuckled. She leaned forward, letting their foreheads touch. Her voice was deep, barely audible. “Tell me how much.” She flipped their positions, all military training and no real effort. Her fingers traced the curves of Serah’s hips, moved to the back of her thighs. She lifted Serah and slender legs instinctively coiled around her lithe waist. It was all so practiced, so routine, as if it hadn't been done _so_ many times before. The word “wrong” jolted through Lightning’s head – wrong, wrong, _wrong_. She pushed those thoughts far into the recesses of her mind. What she and Serah had – what they did – was special. No one on Cocoon could take this away from them. _Not even Snow._

Those crystal blue eyes, half-lidded, looked up at Lightning. The younger girl took her own bottom lip between her teeth, then released. So. Close.

Her hands ran over the sensitive flesh of Serah’s thighs and ass. Their grip became iron. She felt the subtle sigh of Serah’s breath against her. Their lips connected – not a kiss but just barely; a passing brush of lips. “Tell me, Serah.” The soldier ran her tongue over the girl’s lip just once, relishing the taste of sweet lips. “Tell me how much you missed me.”

*****

Lightning plopped down on the couch, kicking her feet up on the arms. After the lovely shower she and Serah took, she threw on a simple black wife beater and her favorite pair of jeans, dark blue and ripped in various places down the legs– her style. She snatched the remote for the TV from the coffee table and turned it on. Luckily for her, she caught the last rerun of the Bodhum morning news – it was only just after ten anyway. She peered over the back of the couch and caught of glimpse of nearly pinkish hair moving around in the kitchen. The sergeant returned to attention to the TV, smirking.

“Liiiight, time to eat!” Serah poked her head into the living room with a smile on her face.

“’Kay.” She remained on the couch, eyes fixated on the television. There was just _one_ major story she was wanted to hear about; breakfast could wait a few minutes.

The younger Farron walked into the living room, blocking the TV. “C’mon, Light, the food’s gonna get cold.”

It was a pet peeve of Serah’s, Lightning knew. Still, she didn’t budge. “It’s just one story, Serah, move.”

She did move, closer to the couch, a hair’s breadth away from the lounging woman. _“Claaaaiiiiirrrree!”_

Lightning froze. There it was. Again. The lip biting, hair-twirling, puppy-dog-eyed facade of _innocence._ How many times would she have to deal with this?

Serah climbed onto the couch, her knees on either side of her sister’s waist. “Come on, Claire. I just wanted you to eat me.”

 _Wait…_ “What?” 

“Were you paying attention, sis? I said I just wanted you to eat with me. Please, Claire? I did not just make you breakfast for you to not eat it.” Her face scrunched into a pout, lips poking out cutely.

Okay, maybe she was hearing things. Then again, she was never sure with Serah. People always assumed that she was the innocent, nice sister. If they really knew, they’d understand that Serah was the _furthest_ thing from innocent.

“All right, Princess, fine.” Lightning smiled. “Get up. Before I make you.” 

“What if I want you to make me?” She poked her tongue out, a seemingly innocent gesture on the surface.

Her eyebrow rose. Was that a challenge? Sergeant Lightning Farron did not back down from challenges, even from her younger sister. “You sure you wanna go there, Kitten?” She trailed her fingers up Serah’s thigh, feeling the rise of gooseflesh on tender skin. For just a moment, she considered reaching up and biting that tongue.

Serah shivered. She pressed a palm on Lightning’s abdomen, using the other hand to pull down the hem of her plaid crimson skirt. “Maybe I do?” She let out a short breath, a cross between a sigh and scoff.

Right. She _was_ challenging her. Lightning smirked. Cute, but she’d finish this later. “What, didn’t have enough in the shower?” She found herself returning the sudden gyration of Serah’s hips just then.

“Oh- I- shut up, Light!” She blushed, cheeks as red her skirt. She untangled herself from her sprawled-out sister and left for the kitchen.

Even after stomping away, Lightning took note of the girl tugging at her white blouse. She finally removed herself from the couch, following her sister. Serah had outdone herself as usual; Lightning sat down at the table and was greeted with a wonderful breakfast before her, her favorite. A stack of pancakes towered on one side of the ceramic plate, complimented by fluffy eggs (egg whites for her, as she always requested) and lean sausages. On a separate plate to the side, there was a handful of assorted fruit – pineapple, blueberry, kiwi, and strawberry.

Serah sat down at the dinner table giving Lightning a warm smile. “Hope you like it, sis.”

Lightning rolled her eyes playfully. “When do I never like your cooking, Serah?”

The Farrons ate breakfast together for the first time in weeks. It was almost odd in a sense, sitting down over a plate of pancakes and discussing their lives as if they did so every day. Lightning preferred it this way and she figured Serah just went along with it. Most of the time. Today, they were planning on seeing a movie, just to get out of the house. Lightning smiled to herself. It had been at least two months since they had any personal time together and- 

“…probably going shopping next week and then I might be meeting up with Snow.”

“…What?”

Serah giggled. “Liiight, were you listening?”

“I- uh, sorry. What were you saying?”

“I saaaiiid, I think I might go shopping with a few friends from school next week. And then I might be hanging out with Snow, I guess.”

The sergeant snapped her head up at the name and scowled. “Why?”

The younger Farron shrugged. “He asked me to hang out.” She took her and Lightning’s cleaned plates and ambled to the sink. “He’s a little intimidating at first, but he’s really nice, Light.”

Lightning followed her. “I’m not intimidated by that behemoth. I just don’t like him.” It was true. It would take a lot for her to be intimidated by anything, really, so a six-foot-seven-inch-tall idiot with stupid chocobo hair hidden under an ugly beanie was the least of her concerns.

Serah pushed past her sister after putting the dishes in the sink. She leaned against the marble counter, folding her arms against her chest and the gossamer fabric of her blouse. Her hair fell over her left shoulder, reminiscent of Lightning’s own, as she tilted her head to the side. The workings of a smirk appeared on her lips, which her sister knew to be accusatory. “Is that all it is?”

“Tch, don’t test me, Serah.”

“I’m not! I’m just saying. You always act so weird when I talk about him. He’s really nice and a huge teddy bear! And I think he likes me.” She rested her hands on the counter behind her.

Lightning clenched her jaw. Oh really?

Either Serah was playing dumb or she really wasn’t paying enough attention to him to actually notice. From what Lightning knew, Serah hung out with him quite often. Every few days or so, she’d get a text from her while at work saying that she’d be gone for the afternoon – ‘out with Snow, be back later.’ The soldier’s heart ached whenever she received those texts. 

“Light, what’s wrong?” Serah sounded somewhere between worried and curious.

“Nothing.” She folded her arms across her chest, hoping Serah would drop it.

…And of course, she didn’t. Serah unfolded Lightning’s arms, causing the woman to growl. “Light, look at- no. Look at me. You’re not jealous of Snow, are you?” She placed a palm on Lightning’s cheek.

As if on instinct, the soldier softened, nuzzling her cheek into her sister’s hand. She wrapped her arms around the smaller girl’s waist and pressed her back into the kitchen counter, then leaned in close to Serah’s ear. “I _don’t_ like him. He’s a bad influence on you. And I don’t want him putting you in danger with that vigilante group he leads. He’s already trouble enough for Guardian Corps.” Without thinking, she traced the outline of Serah’s jaw with her lips. “I just want you to be safe, Serah.”

Serah laughed, just a whisper under her breath. “I _am_ safe. You keep me safe. Besides, who’s to say you aren’t already a bad influence on me, Claire?” 

Her name. Again. The way it rolled off Serah’s tongue so smoothly caused Lightning to have thought after sickening thought of what she wanted to do to her. It was something she learned over the years. When Serah wanted something, all she had to do was ask. The use of Lightning’s real name was a low blow that was thrown all too often (and Serah knew), but even then the hardened soldier couldn’t resist giving her little sister whatever she wanted.

“What do you want?” Lightning purred.

Serah chuckled. Her hand traveled, small fingers wrapping around one of Lightning’s wrists around her back. She pulled the hand closer and closer to the hem of her skirt between words. “I…I just. Want. You.”

“You have me, little Kitten.” Lightning removed her hand from her sister’s grasp. Said hand pawed at the soft flesh of an inner thigh. The sigh that resulted afterwards was heaven upon her ears, encouragement to continue. Gunblade-calloused fingers tugged at the hem of the skirt. They shifted lower, under the fabric. Her fingers ghosted over the lace of Serah’s underwear. She was wet. Oh, so, _wet._ “Is this what you wanted?”

 _“Uhnn- oh, Etro…”_ Serah threw her head back. Her knuckles turned white from her grip on the counter behind her. She grinded her herself into the hand near her center, into the hips that held her in place. Gods she was horny.

“I asked you a question, Serah.” Once more, her fingers ran over her sister, slow and labored. She felt Serah shiver under her touch. “If it’s not what you want, I can stop-ˮ

Serah snapped her head forward. “No! No, please, no.”

“Tell me, Serah.”

“Yes! Yes, I… _fuuuck, right there…_ I want it. I want- I want you.”

Lightning laughed at her sister’s vulgar choice of words; it was unlike her. The soldier relished hearing those dirty things come out of Serah’s mouth. Just then, she wondered what else she could get out of her. The subtle movement of Serah's leg did not go unnoticed; she was granted access and graced with an idea. 

“Claire?” Serah’s voice trembled with want at the disappearance of those skilled fingers.

She leaned in, taking in the wonderful sight of half-lidded crystal-blue eyes, and brushed their lips together. This time it was a kiss – soft and fleeting, yet still passionate. “Shhh… Just relax, okay, Kitten?”

The younger Farron nodded.

The muscles in Lightning’s arms bunched and coiled as she hoisted the smaller frame up, just as effortlessly as before. She sat Serah on the edge of the counter, letting her lean legs dangle above the floor.

“Claire…” Serah reached out to her sister, running her hands on Lightning’s abdomen under the black wife beater.

Lightning flinched under the girl’s touch. Her own hands were busy running down Serah’s back, fingertips tracing every curve and contour of her body. She mapped her back, running down to her waist, hips, finally over her soft belly, under her blouse. She leaned in close and caught her sister’s lips with her own, tasting the sweet savor of honey from breakfast. The kiss was rough, a feral clash of lips and tongue. Lightning dominated the kiss, but it was sending her over the edge. She was a soldier with years of self-control under her belt but it took her all of her willpower to not rip the clothes off Serah’s back and fuck her into submission. While she assaulted the girl’s mouth with rough kisses, her hands moved again, making their new home at the apex of Serah’s thighs.

“Ohhh, _fuuuck…_ ” Serah moaned through the kiss’s break. She craned her neck to the side and her eyes screwed shut.

Taking the movement as an invitation, Lightning continued her rain of kisses, gentler now, along the line of her jaw. Serah smelled wonderful, Lightning took note, still fragranced with the strawberry and kiwi body wash from the shower as well as traces of her own scent underneath. There was something about the way Serah smelled - a light, almost flowery aroma - that made Lightning shake with delight. Moving down to the strawberry-blonde girl’s neck, she stopped and hovered over the junction of Serah’s neck and shoulder. She grazed her teeth over the skin there, and chuckled at the sharp intake of breath that reached her ear.

Serah gasped again. She brought a hand up to her sister’s head, threading her fingers through soft hair, still damp from the shower. Tongue running over her bottom lip, her free hand gripped the counter harder still. Even then, her attention was divided – half of it noticing the way Lightning’s hands played around her thighs and soaking center, and the other half noticing the quick peck on her neck. Then her eyes snapped open. “Waaaait, Claire. Don’t. You’re…gonna-ˮ

“Too late.” Lightning took the creamy patch of skin into her mouth. She sucked on it, licked, and nipped at it. Finally, she bit down on the soft flesh. She was certain she’d left a mark. She didn’t care. Even if it was in a place where Serah could hide it beneath her blouse, all Lightning cared about was that she belonged to her. Every mark she ever left upon her sister was but a small reminder, and every strained moan that ever reached her ear was confirmation.

Serah whimpered. Try as she might to get Lightning to stop leaving hickeys around her neck, it never worked. Once again she trailed the free hand up Lightning’s wife beater, this time, higher, brushing the underside of her breast. She felt a sigh tickle her neck and smiled. Her hand moved again, joining the one tangled in her sister’s hair. She gave a gentle tug and the soldier lifted her head immediately, releasing her neck.

The smirk on Lightning’s face was devilish. Her eyes made contact with Serah’s for a brief second. She pecked the girl on the lips once, then dropped to her knees.

The younger Farron released her grip on Lightning’s hair. “Uhhh, Claire-ˮ

“Sshhh.” The soldier ran her fingertips over each thigh, grazing the skin with her nails. She pressed her mouth on the left thigh. Along the inside of the thigh, she trailed a line of gentle kisses, all the way up to the apex. 

Serah gasped and flung her head back. “Oh, please…”

Repeating with the opposite leg, she muffled between kisses, “Please…what?”

“Please…just- _oh…_ ” Okay, now Serah was sure she felt something moist against her already soaked underwear. She sighed. “Do that again.”

“Again, huh? Why don’t you do something for me first?” Lightning rose. She rested her forehead against Serah’s.

“Dammit, Claire!” Serah groaned.

Lightning only chuckled. She pressed her lips against her sister’s once more, adamant on letting the girl taste a sample of herself.

And she did, just barely, when her tongue slid over her lips. It was a familiar savor – neither sweet nor tangy, but somewhere in between.

Lightning leaned near her ear. She caressed the shell with her lips. Her hands fingered the lace strings of the underwear almost hungrily. “Lift up.”

“’Kay.” She placed her palms on the counter and lifted her hips up just enough for the fingers on her skin to slide her underwear down. The marble was cold against her now bare bottom. Serah bit her lip, eyes fixated on Lightning as she descended once more.

The sergeant wasted no time. She pressed her mouth against Serah, receiving a strained swear in return. “Language, Serah.”

“Shut up…”

Lightning ran her tongue up the entire length of Serah’s center. She should have felt guilty or even disgusting for doing something like this, but she didn’t. She threw those feelings out of the window months ago. She missed Serah more than anything and wanted nothing more than to please the girl; it was the least she could do for being gone so often.

Serah moaned. Her breathing was labored, irregular. She threw a hand on the head of pink, gripping tighter than she ever thought she could.

Though she never said so, Lightning loved it when Serah played and pulled her hair. Just from that, she kissed, lapped, and licked Serah harder, quickening her pace like a hungry cat. The only thing she heard was the wet sound of her tongue and the frantic sighs and moans from her younger sister.

“Ohhh, Claire. Please…faster, please?”

“Anything for you, Kitten,” she whispered. And she did just that. Her pace increased. Serah spread her legs for her once again. As a response, Lightning hooked one arm around each thigh and pulled Serah closer to her, leaving the legs to rest over her shoulders. Good. Easier access.

Serah gasped at the sudden motion. Her nails raked Lightning’s scalp but it wasn’t enough. She needed to grab on to something else! She needed to- _oh_. She lolled her head around in ecstasy, wondering _how on Cocoon_ Lightning could do so much with her tongue. Her legs clamped around her sister’s head. 

Experience told Lightning that her sister was nearing her peak. She slowed her pace just enough to draw the girl out. All she needed now was to-

_BZZZZZZZT!_

The soldier shook once and stopped her ministrations, broken out of her focus. The cacophony of frequent vibration and a terribly sung rock song attacked her ears.

“Fuck…FUCK, SNOW!” Serah reached for her cell phone then stopped. She’d forgotten she left her phone on the counter when making breakfast. Her blue eyes darted from the phone to Lightning and back again.

Lightning scowled. Of all the things that could happen in that moment, it had to have been that _idiot_ calling her sister. To say that she wasn’t bothered by it would have been a lie. Instead of leaving Serah, though, she stroked her tongue up Serah’s entire length. “Answer it.”

“W-What? But, Claire, I- we-we’re…”

“Do it.”

Serah growled. She picked up the phone and pressed the green button on the screen. She brought the white device to her ear. “H-Hello?”

_“Serah, hey!”_

Lightning rolled her eyes. She could hear the behemoth’s voice perfectly.

“Oh, hi, Snow.” Serah relaxed a little.

_“You sound tired. You weren’t sleeping were you?”_

Serah smiled. “No, it’s okay. Why, what’s up?”

_“Well I wanted to know if you were free today. To hang out?”_

Lightning bristled. _Oh really?_

“Oh, I don’t know, Snow, I-ˮ

_“It’s okay, I-I can pick you up if that’s what you’re worried about. I heard there’s this carnival in town and-ˮ_

“Wait, Snow. I- _ohhhh god…”_

_“Serah? Are you okay? Is something hurting you?”_

Lightning smirked to herself as she continued the motions between the legs clamped around her head. Snow was not getting her. Not today.

“No, no! I’m fine. Just stretching.” Serah’s face flushed. On instinct her free hand returned to threading through the fine hair of her sister’s head.

_“Haha, maybe you should stretch more often.”_

Serah just laughed nervously but dismissed the comment. “Uhh, Snow? I’m actually _soo-oooh_ busy today. I can’t hang out.”

_“Really? That sucks. So not even later?”_

She closed her eyes. _“Yeeessss…_ I mean no- I-I mean, no I can’t later. I’m going to be busy. _Ahhh_ -aaalllll day. My sister, Lightning, she came home last night. She’s…off today.”

_“Ahhh, great. So much for that. Tell Sergeant Hardass I said hi.”_

Lightning rumbled into Serah’s thigh. ‘Sergeant Hardass’, huh? _Serah_ could have thought of a better insult than that. Still… She relaxed at the sudden caress of delicate fingers on her head.

Serah’s voice was calmer than it should have been as she spoke, _“Sss_ now…don’t _uhhmm,_ talk about my sister that way. She takes care of me. You know that.”

 _“Yeah, r-right, you’re right. Sorry.”_ He laughed nervously. _“Well anyway, maybe tomorrow then? The carnival was here all weekend and it’ll be the last day. I promise we’ll have a blast!”_

Serah didn’t respond, or rather, it seemed like she didn’t hear him. Her hips bucked into Lightning’s mouth once, then twice.

_“Serah? Serah, are you there?”_

The fingers on Lightning’s head ran through her hair then gripped hard. Lightning flinched. A whispered ‘oh fuck’ reached her ears as Serah came. The cell phone dropped from her sister’s hand onto the counter. She smirked, admiring her handiwork as well as Snow’s frantic yelling over the phone. Her lips and tongue were covered in Serah’s juices. After lapping up every last bit she could, she picked up Serah’s discarded underwear from the tiled floor. She rose and pulled the lace bikini bottom up just to Serah’s knees. Leaning in close to the dazed girl’s ear she whispered, “You might want to go clean up the mess you just made.” With that, she kissed the girl full on the lips.

The younger Farron moaned into the kiss, low enough to (hopefully) not be heard by Snow, but was pushed away. She jerked forward, attempting to catch those lips and taste herself again, but Lightning leaned away. Serah whimpered. Grabbing a fistful of her sister’s shirt, she pulled her close and stole a deep tongue-induced kiss. She moved her hand around the counter and never broke eye contact. Finally getting her phone, she sighed and brought it up to her ear. Snow must have been fuming. “Hello?”

_“Oh hey, Serah! What happened? I was calling for you!”_

“Sorry Snow. I-uh dropped my phone. What were you saying?”

_“I-I was just saying maybe we could go tomorrow?”_

“Right! Um… I don’t know yet. I’ll let you know if I can. Look, Snow, I’m uhh, kinda busy right now so I’ll call you later okay?” She twirled a strand of hair between two fingers.

_“Serah- I- Ugh, fine. Okay then, bye.”_

“Bye.” The phone clicked, signaling that Snow had hung up. Serah turned her eyes to Lightning and glared. “I hate you _so_ much right now!”

Lightning leaned on the refrigerator a few feet from the counter. She stifled a laugh that threatened to escape but ultimately kept her composure.

“On the phone with Snow, Lightning? _Really?!”_

The soldier licked her lips. She could have sworn she saw Serah mimic her. “What? Didn’t like it?”

“I…didn’t say _that.”_ Serah dropped from the counter and fixed her clothes. “I- _whoaa…”_ Her legs wobbled and shook like she hadn’t used them in weeks. Hands flung out for something to hold on to – the counter next to her. 

Lightning laughed to herself. Her sister blushed furiously. How cute. “I’m going to go take a nap before the movie starts since we have a while. Feel free to join me when you can walk again.” Upon leaving the kitchen, she heard an angry groan stumbling towards the bathroom. She threw herself on the couch in the living room, kicking her feet up on the arm as she did earlier. With the remote, she lowered the TV volume to reasonable sleeping level and closed her eyes. In only a few minutes she drifted off to sleep.  
-  
She didn’t know what time it was when she was disturbed, but her eyes fluttered open to just a crack, scratchy and dry. A glimpse of white and pink flashed before her and a weight settled between her legs. Her arm was lifted and moved, positioned over…something warm. She felt a soft brush on her hand. Fingers. They intertwined with hers.

_Serah._

Once again, her eyes fluttered shut. She drifted back into darkness and let sleep overtake her.


	2. Chapter 2

**Summary for the Chapter:**

> Lightning finally has a day off to spend time with her sister, Serah. Lightning knows Serah - she isn't as innocent as everyone thinks she is - but yet the soldier still can't resist her. Farroncest. Written for FFXIII Kink Meme.

**Notes for the Chapter:**

> Title: Bonding - Part 2  
> Pairing: Farroncest (Lightning/Serah), extremely mild Serah/Snow  
> Rating: M for sisterly incest, some language, and very mild D/s  
> Words: 4,508  
> Song Inspiration: "Ecstasy" - Tinashe  
> Prompt Request: "Lightning may dominate Serah in bed, but sex-devious Serah is the one who really pulls the strings in their relationship. Orrrrr simply, Lightning can't resist Serah, and Serah ALWAYS gets what she wants from big sis."
> 
> Disclaimer: Like I said previously, I don't own any characters in this story, nor am I making money from writing this. They belong to their rightful owners. I'm just a bored college kid who likes to write.
> 
> A/N: Here's part two. As you've already noticed, this story really has no plot as the sole purpose was to fulfill a prompt. I'm also hoping that no one is terribly out of character here either. Oh, by the way, this entire fic was my first attempt at writing smut, so I hope it's not too bad. Enjoy!

Lightning ran her fingers through the silk of her sister's mane, strands of strawberry-blonde hair cascading down the teenage girl's forehead and cheek. She had awoken only ten minutes ago to find Serah fast asleep on her abdomen, curled up between her legs. A possessive arm was wrapped around Serah's midsection. She figured Serah moved it but wouldn't have been surprised to have done it herself while asleep. She glanced at the digital clock on the TV. It was after one thirty, with a little more than an hour before the movie started. Lightning didn't want to wake Serah up; she looked too peaceful with her soft, angelic expression and shallow, even breathing. Serah also had a nasty habit of being unbelievably horny after a nap. Deciding against just leaving her, Lightning sighed and gave her a gentle shake around the waist. "Serah. Serah! Hey, wake up."

"Mmmnn…wha…?" Serah huffed a tired, irritated sigh. "Hmm…?" Her head rose from its place on Lightning's belly, giving light to the most confused expression Lightning had ever seen.

A smile crept upon Lightning's face. "Hey. Rise and shine, Princess. We have to go soon."

"Mmmm…" Serah yawned, using her palm to rub the sleep out of her eyes. "Already? How long did we sleep? What time is it?"

"Not long, an hour and a half maybe. It's almost two." She planted a chaste kiss on Serah's forehead. "Come on, sleepy, get up."

Serah finally moved. She rose up to her knees and stretched, letting out a content sigh when she was finished. She lowered herself to all fours in front of her older sister. There was a mischievous glint in her eyes that Lightning managed to catch. "Do we have to go noooww?"

Oh, did Lightning call it. "Yes. Did you want to be late? We are still walking, right?"

Serah put on her best pout. "It doesn't start for another hour! And then previews, you know?" Her voice dropped to a whisper. "Come on, Claire. We have time."

"Serah…" Lightning sighed, trying to ignore the beginnings of desire clawing at her core. It proved quite difficult with her sister on her hands and knees in front of her, practically begging for a little release.

"Please?" Serah inched closer. The tip of her nose brushed Lightning's own and her mouth parted in a grin. A sigh escaped her, brushing her sister's lips.

Lightning stared at her, scanning her entire form. There was an angry red mark on her neck where Lightning assaulted her with kisses just hours ago. The bottom of the blouse that covered her upper half was suspended off her midsection. Lightning figured the small crimson skirt she wore barely covered her ass in this position. Lightning leaned her head back on the couch arm, sighing as she shut her eyes.

Serah inched closer, marking the exposed skin of Lightning's neck under her lips. "Please, Claire-bear?" she moaned, relishing the shiver that wracked the soldier's body at her secret pet name. Serah took Lightning's chin in her fingers and tilted her head forward to face her. Her crystal-blue eyes lowered, tracing the outline of Lightning's lips, then returned to her sister's lustful gaze. She placed a finger under Lightning's chin and lifted, connecting their lips. She mewled into the short kiss, and licked her lips upon breaking contact. The look in her eyes was begging, _pleading._  
  
The soldier tried everything to calm the beating heart in her chest, but to no avail. In that moment she felt self-conscious, like Serah was privy to every budding thought that sprouted in her mind. She glanced at the clock again, not bothering to move her head. They… _had_ time, sure enough. The movie theater was a fifteen minute walk from the house. And even then, they could get there in time on Lightning's velocycle if needed. Lightning hummed. She cursed herself at the triumphant smirk creeping upon Serah's face.

There was nothing more to say; Serah knew she'd won. A hand thrust out, right above the valley of Lightning's breasts, and pushed her back, further into the couch. Both hands rested on the cream felt material of the couch, on either side of Lightning's head. She shifted herself onto her sister's lap, knees resting on either side of Lightning's waist.

Lightning's fingers ran up the sensitive skin of her younger sister's back, lifting the fabric of her white blouse along with it. The look on Serah's face was priceless – her eyes were half-lidded and her mouth twisted into a funny smirk, teeth gripping her bottom lip. Lightning smiled herself, directed more at the cute giggle that escaped Serah's lips.

"Mmm, haha, _Claaaire…"_ Her hips gyrated at an even pace against the soldier's lap. She lowered herself, resting her forehead against Lightning's own.

Lightning chuckled against Serah's lips. "Not my fault you're ticklish." Her hand traveled higher up the ivory skin of the girl's back and stopped at her bra. With acquired skill, her fingers unhooked the garment and Serah's breasts relaxed beneath her shirt. This time, Lightning initiated a kiss. Neither Farron fought for dominance; the kiss itself was heated and intense, equal in passion on both sides. Lightning groaned. Animalistic desire welled into her core, pooling into her center and threatening to escape through Serah's heavy grinding into her lap.

The connection was broken for but a moment as Serah whispered between short, fresh kisses, "We're not gonna be late are we?"

"Not if you hurry up." Lightning drew lazy geometric shapes into the heated skin of Serah's back. Gooseflesh rose beneath her fingertips. She dragged her index across Serah's waist, crossing over to the front of her torso. The finger circled the girl's navel then traveled back up to brush the underside of her breast twice. She took the hand away for a second then flicked the delicate fabric of the blouse. "Take it off," she growled. The force behind the command was unintended, but Serah seemed to take it in stride.

Serah ground her hips into the front of Lightning's jeans once more and purred. _"Mmm…yeeessss, Sergeant."_

Lightning smirked. Her insides fluttered; it had been a while since Serah addressed her in such a way.

In one swift motion, Serah grasped the hem of her shirt and brought it over her head. She removed the undone black bra with it, setting them both over the back of the couch. Her breasts were now in full view before the soldier, coral nipples hardening against the cool air of the living room.

Lightning chuckled, her eyes drinking in every inch of Serah's exposed torso. "Good girl."

*****

The Farrons missed the movie. What was originally planned as a (hopeful) quickie turned into a hot and heavy make-out session. The frisky biting, clawing, and petting ended with a half-naked Serah in a laughing fit on the living room floor under her sister's tickling and kissing assault. It took them nearly forty minutes to get to the theater after fixing themselves up. They decided to catch the next showing available.

Lightning ambled into the theater with Serah close at her side. She scanned the area. Only a handful of people were even there – some purchasing tickets from one of the electronic ticket dispensers, and others hanging around the video arcade. "Not very crowded here today, is it?"

"Maybe everyone's at that carnival Snow was talking about. Isn't that the one that comes every few months?" Serah skipped ahead near a dispenser.

Lightning quirked her head to the side. "Hmph, maybe. I wouldn't mind it being quiet for once." She wasn't one to care much about dealing with large groups of people and preferred to have her day with Serah alone. Out of the corner of her eye, she caught movie posters displayed on a large screen. The poster of the movie they were seeing was pitch black with nothing but a creepy doll on the front. Its eyes were hollow and the grimace on its face gave off an unsettling vibe. Lightning raised a brow. "Hey, are you sure you want to see this movie? It's a horror. You _hate_ horror."

Serah pouted, puffing her lips out. "I do not! I just…prefer watching them with you."

"Hah! I always knew you were just a big scaredy-cat, Serah." Lightning flicked Serah on the head lightly as Serah folded her arms across her chest. "Oh, stop being a baby." It never ceased to amaze her how much Serah acted like her when she was upset. Lightning turned to the ticket dispenser. With a few button presses, she purchased two tickets to the movie.

Serah stuck out her tongue. "I'm not!" She then attached herself to her sister's arm. "But…you will protect me from the scary monsters, right, sis?" She batted her eyelashes.

Lightning smiled, poking her sister in the nose with a finger. "Of course I will, silly girl." She felt the brush of cool fingertips trailing down her bare arm. Serah must have still been suffering from the lack of release after their make-out session on the couch; she'd be shocked if they made it through the entire movie without even touching. "Here." She handed a ticket to Serah. "Don't lose it."

"I won't, geez. Hey, Light, can we get-

"Serah! Serah is that you? Heyyy!"

The soldier knew that rough, booming voice anywhere. Snow. She clenched her jaw. Why did he have to show up here, of all places, while she and her younger sister were trying to spend a nice, quiet day together? Serah had gotten rid of him on the phone earlier…with her help of course, and wasn't expecting to be bothered again. With the arm Serah clung to, she massaged the back of Serah's hand with her thumb, rubbing the soft skin in gentle circles. Her aquamarine eyes cut to Serah. She could have sworn she saw the girl roll her eyes before turning around but that could have been wishful thinking.

"Snow!" Serah detached herself from Lightning's arm, letting her hand linger longer than it should have before pulling away.

"Ugh…" Lightning spun on her heel, rolling her eyes. The behemoth before them wrapped his enormous arms around Serah's midsection. He hefted her up with no effort and spun her around in an uncomfortable-looking bear hug. Etro, why was he so _rough_ with her? Every movement of his arm looked powerful enough to snap a tree branch in half with ease. Serah didn't need anyone manhandling her, especially not some giant beast as wide as a tree trunk. Lightning advanced forward, but stopped when Snow put her sister down.

Snow beamed. "Serah, I missed you! Hey, uh, what's that on your neck?"

Lightning bit her tongue to stifle a laugh.

Serah's eyes widened in horror. She slapped a hand onto the mark that she'd forgotten was on her neck. "OH! Um- I- it's just a rash! Something must have broken me out this morning."She bit her lip nervously, eyes cutting to her smirking sister.

Snow raised an eyebrow but smiled. "Oh, well, okay. Well, what're you doing here? I thought you were busy today?"

Serah hooked her hands behind her back and bounced on her heels. "Yeah! I told you I was hanging out with my sister today."

"Riiight." With that, Snow turned to her. "He-Heyyy, Lightning, lookin' good. Nice to see you out of uniform for once." He smirked, rubbing a hand over the blond stubble on his chin.

"Nice to see you don't look like a homeless bum today, _Snow."_ Lightning shifted her weight to one leg and crossed her arms over her chest, standing rigidly at attention.

"Y-yeah, it's, uh, nice out today, ya know?" Snow laughed nervously. He jammed his hands into the pockets of his heavy grey shorts.

Well, maybe that would shut him up. Lightning locked eyes with Serah, who was glaring crystal daggers at her near Snow's side. Lightning made out her sister mouthing the word 'behave' at her and immediately relaxed. He was lucky that Serah was there to prevent her from decking him in the face at any moment.

Serah's demeanor changed in an instant. "So, Snow. What brings you here? Are you seeing a movie too? You're not usually the type."

"Oh, uh, yeah. Maqui wanted to see this sci-fi flick that came out yesterday. The kid doesn't have many friends as it is so I said I'd take him. I mean, he _is_ like my little brother."

"Aww, aren't you nice?" Serah cooed. "What time does your movie start? Ours should be in about a half hour."

"Soon. Just waiting for the kid to come back from the bathroom. He's been in there forever. Then again Gadot did cook dinner last night…"

Lightning couldn't take the small talk any longer. "I'll be back, Serah."

Serah turned to her. "Oh, Light? Can you get me popcorn, please?"

"Sure." Lightning shoved her hands in the pockets of her sleeveless, crimson hoodie. She stomped over to the concession stand's line and huffed. Snow was getting on her nerves just by breathing the same air as her. She had no idea how someone on this planet could ever be that annoying. How did Serah even stand him? Lightning glanced back at the two and immediately regretted it. They were standing close to one another. Serah was giggling, the fakest laugh ever, Lightning knew, but she was laughing regardless. To make matters worse, Snow didn't notice a thing; he didn't pick up on how only one of Serah's eyes scrunched up in that laugh with just the subtle rise of one side of her top lip. He stood there and accepted that fake laugh as a false boost to his already overinflated ego. Serah and Snow then embraced in a tight hug. Lightning turned away, disgusted, after catching a glimpse of knowing sapphire eyes. She turned her attention back to the concession line and folded her arms once more. She sighed, narrowing her eyes at the three moviegoers in front of her.

Lightning gritted her teeth. She was hoping the behemoth would be gone by the time she reached the counter. Two more people to go now.

"What's got you so worked up?"

The hardened soldier flinched. Serah's familiar timbre reverberated in her ear, making the hairs on the back of her neck stand on end. "Dammit, Serah, don't sneak up on me like that!"

"Something's eating you. What's wrong, sis? You would have noticed me any other time." Serah moved next to her in line.

"Nothing."

The girl pouted. "Here we go with this again. Was it Snow?" Serah snatched her sister's hand and laced their fingers. "Lightning, tell me."

Lightning knew Serah would not dare use her real name in front of others, but the meaning was just as clear now as it was before. "I'm so sick of him, I just-"

Serah pinched the bridge of her nose. "I'm not going through this again today." The younger Farron stepped out of line, yanking her sister with her.

"Se-Serah, what are you- hey!" Lightning stumbled behind her, an ungraceful display of her usual flawless mobility. She had no idea what was going through Serah's mind at the moment. The thought of that actually frightened her to an extent. Lightning was dragged into the women's restroom as Serah's hand tightened around her wrist. She was blasted in the face with the combined stench of urine and hand soap. They pushed past a confused teenager, face caked with makeup, who all but bolted out of the area.

Yanking Lightning forward, Serah threw her into the last stall, one reserved for the handicapped. Without looking, she shut and locked the grey door behind her.

Lightning's eyebrow rose. "What are you doing?"

"I am so _tired…"_ Serah advanced, pushing her older sister into the space of cool grey wall beside the low toilet. "…of you comparing yourself…" She pressed her body hard into Lightning. "…to _Snow."_

She wasn't comparing herself to Snow…was she? She shook her head. "Why would I compare myself to _that idiot?"_

"Don't give me that! You may not be saying that outright, but I know you are!" Serah hissed.

The soldier growled. "Tch. Yeah, right. You just deserve better than _him,_ that's all." She turned her head to the side.

"See? I knew it! Stop being so _jealous,_ Lightning." Serah pecked her on the lips. "You _know_ I love you, sis. More than anything on Cocoon. Snow's a cool guy, but he isn't you. He'll _never_ be you. You're my soldier, Sergeant." Serah's hand descended, fingers playing around with the buckle of Lightning's studded belt. "Do I have to remind you?" After a few tries, she moved the strap through the hoop, unfastening the belt from Lightning's shredded jeans.

Lightning swallowed hard. She scrutinized Serah's every movement. The girl was bold, she'd give her that, though this wouldn't be the first time they'd done something out in public. She exhaled through her nose, blowing a few stray strands of her sister's hair. A small hand roamed up her abdomen before dipping into the front of her jeans. Two fingers traced the middle of her boyshorts. "Nnng…"

"Ooooh, you're getting wet, sis. Is there something you want to tell me?" Serah's voice was low, hushed, barely audible. She removed the hand and palmed the front of Lightning's jeans.

"Serah…" Lightning's eyes were low. She wasn't as vocal as Serah was, but her near silence was identical in meaning. Gods, she wanted it right then and there.

Serah smirked, a mischievous smile plastered on her face. Slow and steady, her hand trailed under her sister's black beater over her taut belly. She lowered herself and lifted the shirt. Her tongue flicked out, tasting salty skin.

Lightning jerked at the light touches. A small laugh escaped her, followed by the pinching of teeth against her skin on her belly. "Hey!" she hissed.

Serah stopped. "What are you laughing for? This isn't funny. I'm still mad at you."

Aquamarine eyes darted from Serah to the stall door. The coast was still clear, but that didn't stop Lightning from shushing her sister. "Why are you so loud?"

"And why are _you_ still talking then?!"

Lightning narrowed her eyes. She pressed a finger to her lips to shush the girl, even though she knew Serah could give a damn less about being caught; they never had been before, even in some particularly risky places.

The younger Farron rose. She leaned her head up close to Lightning's and stared deep into her eyes. _"You_ shush!" She crushed her lips to Lightning's own.

With a free hand, Lightning reached around and cupped Serah's ass beneath her skirt, squeezing hard. She pulled away from the kiss only to lick Serah's bottom lip afterward. "Hurry up and finish." The sound of the restroom door opening caught her ear. A dark shadow moved near the door then back, accompanied by the sound of heavy footsteps.

Serah heard it too. She glanced back at the door, seeing nothing, but perked at the sudden sound of rushing water. With a quick roll of her eyes, she met Lightning for another deep kiss. Her fingers descended to the denim jeans as she ground her hips into the hand on her ass. Slowly, she lowered herself, marking Lightning's torso with kiss after lick. A light trail of saliva lingered in her wake. She grazed her teeth over the soldier's navel, tongue flicking the lightning bolt-shaped stud – her own idea for her sister's belly piercing. Serah knelt in front of Lightning, the skin of her knees cooled from the chilly restroom floor.

Lightning expelled a breath through her nose again. Her stomach fluttered under her sister's touch. Serah was so soft, so gentle with her that Lightning couldn't help but smile. Her jeans loosened. She knew Serah had them unbuttoned and seconds later, they were unzipped. The jeans were dragged to her knees. The hardened soldier shuddered in anticipation.

The rushing water stopped. The restroom door squeaked open, slammed shut, and then all was silent.

"So, _Lightning…"_ Serah breathed hard on Lightning's underwear. She tugged on the light, cobalt fabric, the nails of both hands scraping against the sergeant's hips. "Think I can make you come before the movie starts?" She pressed her nose and mouth against Lightning's center.

"T-Try me."

"Haha, cocky, huh?" Serah's fingers dipped into the waistband of Lightning's boyshorts. In one swift motion, she yanked them down to meet the jeans just above her sister's knees. Serah inhaled deeply. "I bet I can. This should be fun."

Lightning lowered her hand to pet Serah's head before grasping a fistful of hair between her fingers. "No hands."

"Okay, fine. No hands." She rested them on Lightning's behind. "Promise."

"Get started then."

Serah flicked her tongue out and was rewarded with a rolling of hips. "You know I love it when you boss me around."

Lightning didn't respond, or rather, she couldn't. She was already drifting into ecstasy and suffering from hypervigilance. All her senses were heightened; every insignificant sound echoed in her ears and even the slightest of movements registered in her field of vision. There was no one else in the restroom with them, but the thrill of possibly getting caught in public heightened her pleasure. She looked down upon feeling a sudden jerk.

Serah stopped for a split second. "Relax, Claire, no one's coming."

If only she could believe that. The soldier rested her head against the tiled wall. Serah was absolutely wonderful with that tongue of hers. She assaulted Lightning's center with long, even strokes just the way she enjoyed it and- _"Aahh…shit…"_

In a second, Serah changed pace. She drove her tongue deep within Lightning once, twice, then ended with a quick kiss. Her own lips captured and sucked on the woman's clit.

Lightning squirmed in place, sighing. Without thinking, she stroked Serah's head and pushed her closer into herself. She earned an annoyed whimper from the girl below her but paid it no mind.

Serah shifted uncomfortably on the floor. Even though her knees were beginning to ache from the hard tile, she pressed on. Her hands moved from Lightning's ass to her thighs. One hand pried a thigh open, pushing the leg just enough so she could have better access. _"Mmm..."_

"Serah-"

"I'm not!" Serah had a history of cheating in their little 'games.' She knew Lightning would always get her back if she did (though most of the time, she didn't mind her sister dominating her as punishment).

The elder Farron shut her mouth and dropped it. The next second she saw darkness; her eyes closed and she only focused on the pleasure Serah gave her. The ministrations were becoming more random, less static. She didn't know what to expect anymore. Long tender strokes followed short violent ones, dipping followed licking and lapping, and there was the rare apologetic kiss.

Serah slowed her movements and then sped them. Her tongue worked around every crevice, ran over every fold. The subtle tanginess of her sister coated her tongue.

_"Aaah, fuck… M-More…"_ Lightning's breathing was erratic. All of her senses were shutting down one by one. A strained moan rumbled in her throat. _"Ssserah…"_

Serah chuckled through her nose. Her voice was soft as she spoke, "I love it when you're begging me for more but-" She dipped her tongue in once. "I love it more when _you_ control me." Serah fingers moved from Lightning's thigh. She teased around the sergeant's opening before plunging in two fingers. She relished hearing the sharp intake of breath and feeling Lightning's hand tighten its grasp on her hair. With two fingers thrusting at an even pace, she continued running her tongue over the folds.

"Serah, oh _fuck…"_ Lightning was beginning to lose all feeling in her legs. She trembled but felt a stabilizing hand press hard against her belly.

"Almost there," Serah whispered.

Serah knew Lightning too well; she was _indeed_ almost there. Lightning's hand dropped from Serah's head and hung limply at her side. Her eyes were squeezed shut and none of her other senses functioned. She saw nothing, heard nothing, smelled nothing, and _fuck…_ With a barely contained groan, she jerked into Serah's mouth and fingers multiple times. Her body was blazing and tight, and of everything else, she knew nothing.

A smile grew on Serah's face at Lightning's body tightening around her fingers. Serah lapped at her greedily, careful not to miss a drop. Her tongue traced and licked up every last drop of juice, even the line trailing down Lightning's left leg. She removed her fingers with care, running her tongue over them and the webbing of skin between. With her fingers clean, she hooked her thumbs in the waistband of the underwear and pulled them up over her sister's lithe hips. She did the same with the jeans and fastened them as they were before – button, zipper, and studded belt. Fixing Lightning's wife beater and sleeveless crimson hoodie, she rose. She checked the time on her phone before locking eyes with Lightning's glazed own. She smirked. "I think I won."

It took nearly two minutes before Lightning came to and focused on anything. Her heart rate was decelerating and her breathing was returning to normal. It had been too long since she felt anything that intensely gratifying. She gave Serah a grateful smile and peck on the lips. Her smile morphed into an impish smirk. "I…I think you cheated."

"N-No I didn't! Besides, you were barely paying attention. It's not like you would have known!"

"Right. So you did. You're such a terrible liar, Serah."

Serah furrowed her brows. "H-Hey, I-"

The restroom door swung open. Lightning immediately silenced Serah with a crash of her lips. Her eyes tracked a small shadow from under the stall door. It moved near the sink and hovered there for a minute.

Serah turned her head for a second to look but Lightning brought her back. She nodded at the soldier's finger on her own lips but couldn't resist flicking her tongue out. Lightning's arm snaked around her waist and Serah relaxed into it.

Another minute longer and the shadow moved away. The sound of the restroom door closing reverberated in the soldier's ears. "I think we got lucky this time around."

The younger Farron nodded. "Not like last time. _That_ was a close call." She pulled away and yanked Lightning's wrist. "C'mon, the movie's just about to start!"

Lightning pulled her back into her arms with ease. "Hold on, Kitten. You cheated." Her hand grazed over the curve of Serah's ass and squeezed. She brushed up against an earlobe. "Your ass is mine when we get home."

Serah chuckled. _"Yes, Sergeant."_ Serah's hand ghosted down the entire length of Lightning's arm. She then pulled away to unlock the stall door and walked out without a care in the world.

Oh, yes, Serah _would_ be hers when they returned home – _all hers._


	3. Chapter 3

**Summary for the Chapter:**

> Lightning finally has a day off to spend time with her sister, Serah. Lightning knows Serah - she isn't as innocent as everyone thinks she is - but yet the soldier still can't resist her. Farroncest. Written for FFXIII Kink Meme.

**Notes for the Chapter:**

> Title: Bonding - Part 3  
> Pairing: Farroncest (Lightning/Serah), implied Serah/Snow  
> Beta: AQA473  
> Rating: M for sisterly incest, language, very mild D/s  
> Words: 7,663  
> Song Inspiration: "The Worst Guys" - Childish Gambino  
> Prompt Request: "Lightning may dominate Serah in bed, but sex-devious Serah is the one who really pulls the strings in their relationship. Orrrrr simply, Lightning can't resist Serah, and Serah ALWAYS gets what she wants from big sis."
> 
> A/N: Well, guys, here it is. If you're following me on tumblr, then you'll know why this took so long to come out. Anyway, it's here and I had no intentions on abandoning this piece. Like before, this is just a huge smut fic separated into three parts so don't try looking for a story here. Huge, huge thanks to my beta for taking the time to read this, because I have no idea where this fic would be without that massive amount of help. So, I hope you guys are pleased with the final installment, if any of you are even still reading, haha. Reviews are always appreciated, and lyrics mean nothing here, just needed the music. Enjoy!

"What's taking so long?" Serah whispered, breath caressing Lightning's ear. Her fingers ghosted up Lightning's back under her shirt, coaxing a shudder from the older woman.

Lightning twitched and flicked the hand away, shifting the phone to her other ear. After the little stunt at the theater earlier, Serah was well past horny, cold fingers brushing over the ridges of Lightning's spine. Lightning was in the middle of ordering a pizza, gritting her teeth just enough to get most of the order out over the phone's staticky reception. The younger Farron's fingers made it up to Lightning's bra mid-order, and Lightning reached back, pinching the girl in the side.

"Ow!" Lightning didn't have to turn to know Serah was pouting.

Upon finishing the order and hanging up, Lightning stood up and faced her sister, noticing the girl had changed into something more comfortable, a simple tank top and light shorts. "You are such a little minx, you know that?"

"All for you, sis." Serah snatched Lightning's hand and dragged her to the living room. "Here, sit. I need you to help me with something." She then left the room.

Lightning sat, one leg dangling off the couch. She reclined and waited, eyeing a rectangular patch of red-gold on her jeans. The evening sun just barely shone through the windows of the living room. Not long ago, they'd returned from the movie, two hours and fourteen minutes of pure disappointment. After that disaster, neither had the desire to cook, so it wasn't until they stepped in the house that Serah suggested pizza. It was a favorite of theirs to share and perfect for winding down after their day together.

Serah finally returned with a white device clutched in one hand, her fingers tapping away at it with the other. "Hey, Light? Umm, can you help me with my homework?"

Was she serious? Homework? Lightning threw her arm over the back of the couch and smirked. "No. You're smart enough, do it yourself."

"Geez, you're mean. C'mon, please? Don't you want me to graduate?"

"Fine, fine. Yeah, I'll help, if it'll get you to go to college, genius."

"I  _am_ going to Eden already, thanks. Now, move." Serah pushed Lightning's leg over and climbed onto the couch. She tucked her own legs under her and sat against her sister.

Serah was warm and soft against Lightning's front, and she didn't hesitate to snake an arm around her waist and pull her closer. She brought the dangling leg back onto the sofa as she spoke.

"What do you need help with? It must be serious if you're actually taking the time to ask me." She caught a glimpse of the device Serah held in her hands, a small notebook, just a bit larger than a tablet.

"Ugh. Some really stupid paper my Literature teacher is giving us."

"Your Advanced Placement one? Serah, you're graduating in a month, why do you still have homework? In that class, no less."

"It's our last paper. It's easier than that research paper we had due a few weeks ago." She trailed fingertips along the arm wrapped around her waist. "We have to write a paper on someone we know that makes a contribution to Bodhum. So, clearly, I chose you."

"You 'chose' me, huh?" Lightning scoffed. "What, civil servant Snow wasn't good enough for you?" Surprise, surprise.

Serah responded with a click of her tongue. "Shut up. That's why you're upset all the time. I just need to ask you a few questions, and then I'll finish the rest later." She opened up a word processor on the notebook. Her fingers tapped away on the touch screen as she began the workings of an essay.

"Questions," Lightning stated, drawing the word out. "About?"

The girl finished typing up a perfect sentence before she responded. "Guardian Corps. Like, what do you guys do?" Serah placed each hand on Lightning's thighs to lift herself up and shift positions. She brought her knees up closer to her chest, but let one hand linger to caress the fabric coating her sister's thigh.

Oh. Her job. That was simple enough. "I can give you the gist of what we do, but don't expect me to go into extreme detail about any assignments."

"That's so boring! Maybe I should have asked Snow."

Lightning narrowed her eyes and pinched Serah in the side. "Do you want to get this paper done?"

"Okay, okay, fine! I was just kidding. Just tell me. I'll stretch it out somehow." Serah bit her bottom lip and gave Lightning her full attention, though unable to turn around.

"Uhh…wow, where do I start? Right. Guardian Corps is basically responsible for maintaining peace on Cocoon. There are six divisions of GC. The one I'm in would be Bodhum Security Regiment, but you should already know that." She stopped for a moment to watch Serah, who was typing away on the notebook. Nothing fancy yet, just bullet points of core information aside from the initial sentence.

"Okay, continue." Serah shifted again, leaning back further and sitting more upright between her sister's legs.

"Our sole job is to make sure that Bodhum is safe. You know that as well."

"Right, right. But, what do you  _do?"_  The motion of her hand became lethargic, slow and tantalizing, a genuine tease if there ever was one.

Lightning had only barely noticed those tricky fingers on her thigh but dismissed the touch as innocent boredom. "We catch and stop criminals, and we take care of the wildlife that gets out of hand just outside of the city's borders. But, we mostly just do basic patrols around the city. You've seen me near your school a couple times."

More tapping. Serah's voice was a concentrated whisper with her reply. "Uh huh. Keep going." She stopped once more, drawing lazy circles in denim, and pressed herself into Lightning's chest.

"That's…basically it. What more could you want?" The elder Farron rested her chin on her sister's head, face twitching at the strawberry-blonde hairs that tickled her nose. Serah's ministrations became more noticeable to her now, and yet, she still paid them no mind. She'd know if things were about to escalate.

Serah hummed. "Have  _you_  ever caught any criminals?" She shifted her fingers from the leg beside her to the hand on her belly.

Feather-light touches ghosted the skin of Lightning's hand and the light hairs of her arm. She wanted to smile at the question, seemingly innocent on the surface, then recalled that she'd never told Serah much about her job. Serah worried too much, a trait she inherited from their late mother. She sighed.

"I have. Twice."

"What happened?"

The sergeant faltered. "The first guy? Just a common jewelry thief. He gave up quite easily after I chased him around the block. The second?"

"Mhmm…" Serah cuddled closer, tilting her head up just a few degrees. She stretched her legs out.

"Another robber. He was armed. I had to get two of my subordinates to distract him before I was able to take him down. He robbed a small bank near your school."

"Really?" Serah whispered, her fingers intertwined with Lightning's own.

"Yeah."

"I'm glad you're okay. He could have shot you."

Lightning chuckled. "I'm fine, clearly. It's my job. I do what I have to to protect people like you." Her eyes darted in front of her to where the notebook lay on the couch.

Serah's voice was low, an almost velvety rumble from the pit of her throat. "People like  _me_?" She rested her cheek against Lightning's throat, shivering at the vibration of the equally low response.

"Yes. People like you. Civilians."

A short whine escaped Serah's throat. "I'm just a civilian to you, sis?"

"Civilians  _and_  you," Lightning corrected. "You get special protection for being my little sister. And my little kitten." The small hand on hers teased, dragging up Serah's body under her thin shirt. Without looking, she recognized the gentle curve and swell of Serah's breast under her fingertips.

"Mmm, I do?"

Lightning answered, lips not even a hair's breadth away from Serah's ear. "Yes, Serah. You know I'd protect you from anything." Her hand was guided further, now completely covering one breast. A hard nipple brushed the webbing between two fingers, and a sharp hiss caught her ears, cutting the silence of the room in two.

"Anything, Claire _?"_  Serah breathed.

Serah's skin burned under her touch. Lightning caught an ear between her teeth and dragged them, gently, from top to lobe.

"Yes.  _Anything_."

She trailed her lips from Serah's ear to the back of her neck, planting soft kisses along the way. Serah was near writhing under her touch, shivers wracking her body. "I'd rip Cocoon out of its cradle in the heavens if it meant keeping you safe. Remember that."

"Claire-bear?" Serah tilted her head back, closing her eyes. She led her sister's hand further down her body over every curve of smooth skin, past her navel to the waistband of her shorts. "You promise?"

Lightning chuckled into the crook of Serah's neck, kissing a trail back to her ear. "Yes, Serah, I promise." She felt her hand being guided into Serah's shorts, her fingers caressed by her sister's warmth. The body in front of her shuddered, and Lightning's hand was torn away.  _Such a tease._

With Serah's hand dropping along with Lightning's, Serah suppressed a moan. She tilted her head up and to the side, hazy sapphire eyes locking with her sister's wanton gaze. "Mmm, gimme a kiss," she purred.

Lightning wasted no time capturing Serah's lips. Her hand rose, tracing the outline of Serah's flushed, luscious neck, before cupping her cheek. She took her time delving into the familiarity of Serah's mouth, tongue brushing every inch.

Serah moaned into Lightning. She pulled away, a string of saliva connecting the two, and whispered against her soldier's lips.

"So glad I didn't go ask Snow."

"Why's that?"

"I don't think it would have gone this well."

"What? Something like this happen before?"

A deep kiss and chuckle from Serah. "Maybe."

"Right. So you come back here and kiss me with that same mouth like it's okay?" Lightning nuzzled the girl's neck and took in her sweet scent. She grazed her teeth along the pulsating jugular, evidence of her sister's quickening heart rate.

Serah sucked in a breath. "Mmm…please don't be mad." Her eyes shut. "I… _ahhh…_ like your kisses better." Serah's face flushed a deep pink.

Normally, Lightning would have been upset, seething actually. But this time was different. Much different. Serah moaned for her, writhed for her, called  _her_ name. In their most intimate moments, Lightning gave her direction and Serah would follow suit without question. Serah was hers and hers alone. Whatever Snow thoughthe was getting into was all a farce. And Snow could very well go fuck himself.

Lightning smirked into her sister's neck. "You do, huh? Prove it."

Serah snatched herself away from Lightning's grasp. She turned in her seated position and rose to her knees, never breaking away from Lightning's attentive stare. Snatching each of the soldier's hands with her own, Serah pinned them to the arm of the couch beside Lightning's head. Her face was a hair's breadth away from Lightning's, their heated breaths mingling in the closed space. Serah searched her sister's eyes, catching Lightning's lips in her gaze, before mashing their mouths together.

The sergeant was taken aback by the rough, open-mouthed kiss, but melted into it. Serah dominated any of Lightning's attempts at taking control. Lightning refused to fight the tongue brushing every inch of her mouth, welcoming it instead. Etro, she swore she could have gotten drunk off Serah's more intense kisses; they were brusque and controlling, the complete opposite of Serah herself. Lightning considered herself lucky to be the only person able to see this side of her little sister.

"Someone's a little rough today," Lightning whispered through a break in the kiss.

Serah just chuckled, uttering words between kisses. "Your fault. You just- get me so…  _hot_."

She let go of Lightning's hands to lower one of her own between their conjoined bodies while the other pressed against a shoulder. Serah never skipped a beat with her kissing. Her roaming hand tugged at her sister's belt before traveling upwards under her shirt.

Lightning's muscles twitched under her sister's gentle touch, a direct contrast to her aggressive kisses. She grinned at how frisky Serah had been over the course of the day. Normally, the girl would be eager for a session or two after being deprived for weeks at a time but this level of sexual appetite was unheard of. Not that Lightning minded, of course. She welcomed the stress relief and comfort their unions brought with open arms, quite literally.

She felt Serah's lips and tongue slow their advances, almost lethargic, nearly stopping. Lightning fell into an ecstatic trance, and nothing else mattered when Serah brushed her tongue over her lips. Wait, was that- no, never mind; she was just hearing things.

The kiss deepened, and then there was nothing. The weight on top of her disappeared. Lightning's eyes shot open, and she caught Serah walking out of the living room.

"The food is here, sis!"

Ah. So that's what that sound was, the doorbell. Lightning sighed, a little more than irritated at having been interrupted in such an intimate moment. Fixing herself (including the undone belt that Serah was responsible for), she followed her sister to the front door, greeted by a tall, smirking teen with hungry eyes set on Serah.

*****

It was after dinner and Lightning was still seething. Maybe she was being irrational, maybe she shouldn't be so angry over someone she didn't even know, but the awkward silence over dinner upset her sister, and rightfully so, she admitted.

Lightning sank further into the couch, angry eyes glaring at the news on television. She paid it no mind, only focusing on the fact that Serah would dare flirt with some kid right in front of her face. The more she pondered over it, the more ridiculous the entire ordeal seemed. She huffed, blowing strands of hair away from her face. Out of the corner of her eye, she saw Serah turn towards her.

"What is your problem?"

She cut her eyes to the owner of the voice before facing her. "I don't know what you're talking about."

"Oh, really? So you crossing your arms over your chest right now is just nothing?"

Damn. She had and didn't even notice. Serah knew her mannerisms far too well.

Serah mirrored her. "You're upset. Please do not tell me it's over something as trivial as the delivery guy."

Yeah, it sounded completely absurd to be this unnerved. Snow was another story, but to have an incident like this happen twice in one day? Lightning was never one to care much about other people, but when it came to Serah, a different side of her reared its ugly head.

"First Snow and now this. What do you have to say for yourself, Lightning?"

That voice. Every once in a while, Serah exhibited a tinge of stern command in her otherwise light timbre that would have easily rivaled any of the soldier's superiors. It threw Lightning off at times but gave her a welcome shiver up her spine. It proved hard not to smile at being "scolded," but she kept her composure as Serah narrowed her eyes at her.

"It wasn't my fault."

Serah tilted her head to the side. "Are you implying it was mine? Because I was not flirting with him, if that's what you're getting at. I go to school with him."

Lightning scoffed. "He was flirting with you."

A light pink dusted Serah's cheeks. "He…was not! You didn't have to go off on him." She scooted closer and climbed onto Lightning's lap, legs on either side of the elder Farron's waist.

"Shouldn't have looked at you like a piece of meat."

Serah covered her mouth, attempting to hold back a laugh. "Etro, you are so…possessive."

Lightning frowned. She wouldn't have described it in such a way, more like overly protective. That sounded a lot more positive than being possessive; Serah wasn't some object to covet.

"You know, Lightning." Serah pressed her nose into Lightning's neck and dragged her tongue over her pulse. "You're so lucky I like that about you."

Flattering, to say the least. Lightning gripped Serah's ass as she tilted her head back, causing Serah to recoil. "I'm… not trying to be overbearing, but… I don't trust some people around you. You're still my little sister, you know."

Serah's eyes lowered, head tilted. "Lightning." She ran a finger under Lightning's chin and lifted it to meet Lightning's gaze.

Lightning swallowed the lump in her throat. Serah shifted in her lap, and Lightning's hands held her in place at the waist. Lightning admitted that the intense gaze threw her off. Had what she said really been  _that_  bad?

" _Claire…_ "

She winced.

"…you just don't realize how jealous you really are. Has your time away from me taken a toll on you?" Serah cupped Lightning's cheek in her palm. "Doesn't matter. I think I have just the plan to take your mind off everything else."

Lightning searched her sister's eyes, hoping that Serah meant what she imagined. A thumb brushed across her lower lip, teasing, before the smaller, more delicate hand cupped her chin. Serah leaned in, breath tickling Lightning's lips and nose. Lightning made the first move, smashing their lips together in desperate fervor. Her hands roamed of their own accord, pawing at the thin excuse for fabric separating her and the delectable flesh beneath. If Serah wanted a distraction, Lightning was more than happy to deliver.

Serah chuckled into the kiss, brushing her tongue in every reachable corner of Lightning's mouth. She stole Lightning's hands away and pinned them to the back of the couch. The kiss broke, and she uttered words within the confines of the space between them.

"Uh-uh. I have a better idea."

Brows furrowed. Lightning never enjoyed being restricted movement, but if Serah had something better in mind, she'd comply. Lightning stared expectantly, eyes roaming every curve of the girl atop her.

Serah released Lightning's hands, pushing her further into the couch at the shoulder. "Don't move. Watch."

Lightning obeyed, leaning back. Serah's teeth grazed her bottom lip, and she righted herself on Lightning's lap. Serah's eyes focused on her, and Lightning knew what she was up to. It was something the younger Farron did every once in a blue moon, a little reminder for Lightning. Lightning was aware that she often fell prey to jealousy, sometimes to a degree that thoroughly amused Serah, to her own dismay. Loathe to admit, Lightning knew this was Serah's way of keeping her in check. Regardless, that wouldn't stop Lightning from studying the confident movements from the girl on her lap.

Serah's hands explored her body, curious and unwavering. One hand reached under the shirt she wore. Lightning made out that Serah pinched a nipple, and Serah moaned. Her other, however, busied itself into her shorts.

Lightning felt a lump form in her throat at the sight. She ran her index finger up from Serah's navel, but didn't get further than that. Serah snatched her wrist, yanking it away and pinning it to the couch.

"No. Touching."

Serah's voice had dropped. It surprised and excited Lightning all at once as she stretched her arms out across the top of the couch. She kept her eyes fixated on her sister, darting over every visible inch of her. She'd play Serah's little game for now, she decided, as a sly smirk played across her lips.

"Fine."

"Good. Now-" Serah cupped Lightning's chin, directing her gaze to meet her own eyes. "-watch me."

With that, Serah was back into her trance. She bored holes into Lightning with her eyes. Rocking on the soldier's lap just once, she brushed her hand up her shirt, lifting the fabric just enough for Lightning to catch the underside of her breast. With a short sigh, Serah flashed a quick smile.

Lightning's breath caught in her throat.

Serah continued her exploration. One hand trailed up to tweak one breast – making sure that Lightning could see – before grazing the tip of the other.

"You know, Lightning…"

The elder Farron lifted her chin in acknowledgement.

Serah allowed her fingers to brush over Lightning's cheek. "Green is such a nice color on you."

Ha ha. Jokes. Lightning had no time for it, and the scowl on her face was evident of her mood. Even still, she leaned into her sister's gentle touch.

"You're so cute when you pout."

Lightning narrowed her eyes.

"All I'm trying to say is-" Serah slipped two fingers into Lightning's mouth, and Lightning greeted them without complaint. "-you should stop being so tense about me."

Kind of hard to do that when guys were always breathing down her neck.

"Everything you could ever want is right here." She retracted her fingers, guiding them into the front of her shorts. A guttural moan rumbled in her chest as she glided slick digits over herself. "All for you."

Oh. Fuck _._

Lightning shifted uncomfortably, very much aware of Serah's heat on her thigh. She balled fists at her sides, attempting to keep herself under control. Serah was indeed busy pleasuring herself right on her lap, and Lightning could do nothing about it. It was no secret that Lightning enjoyed the little show. Serah had done it a few times before, and the first time caught her off guard in the best way possible. Even now, a few times later, it still put her on edge.

Serah's wet fingers rose to her navel, and then returned to her shorts. She sighed and closed her eyes. Leaning forward, she rested her forehead against Lightning's, and brushed her free hand up her sister's tank. Lightning steeled her jaw as Serah continued to press fingers against herself, speed gradually increasing. Serah moaned into Lightning's lips, brows furrowing in focus.

"What are you thinking about?"

It took several seconds before she was graced with an answer through gritting teeth and curled lips.

"You."

Lightning had assumed. "Doing what?"

" _Unngh_ … Everything imaginable." Serah ground herself into Lightning's lap now. She turned her head, now cheek to cheek with Lightning, lips grazing her ear.

Why not draw it out a bit longer? "Like what? I want specifics."

"Did I finally get your attention?" Serah whispered, chuckling. Her pace decreased a fraction, which Lightning figured was just the right speed to keep her going but not send her over the edge just yet. "You. Everywhere. Pinning me against the wall, bending me over a table, bouncing on this couch. Fucking the breath out of my lungs with your fingers." She gasped. "I love those fingers, Claire."

Even with her limited range of movement, Lightning nipped at Serah's ear, earning a throaty groan in the process. "Yeah? Where do you love them?"

Serah sucked in a quick breath, and stopped her movements altogether briefly. "In my mouth. And inside me."

"Oh, really? Do you want that?"

The younger Farron nodded.

"Show me how much."

Serah obeyed, quickening the pace between her legs. She pressed her forehead against Lightning's cheek, using her other hand to drag nails through Lightning's rose tresses and down her neck. Serah nearly ground herself into the soldier's lap, and Lightning could tell how desperate she was.

"You want it that badly?" Lightning mused.

Serah rolled her hips once. "Yes. Just make me come, please?"

A shiver rolled up Lightning's spine at the husky voice in her ear. She had no intention of denying her sister that request; Lightning's eagerness was evident in her quivering hand shoving familiar, damp fingers into her mouth. Her tongue coated in a sample of Serah's arousal, she licked her lips and brushed her nose against the girl's cheek. Serah responded in kind, dragging lips across the line of her jaw, before planting one gentle kiss on the corner of Lightning's mouth.

Lightning took the opportunity to stand, securing Serah's legs around her waist as Serah herself locked her arms around Lightning's neck. It didn't take long before they reached the soldier's room, and Lightning set the smaller body down on cobalt sheets.

Serah rolled onto her belly, turning her head to give Lightning a look that lit her insides on fire. Lightning flicked her bottom lip with her tongue, inching closer and feeling the brush of Serah's ass against the front of her jeans. She traced a hand up Serah's arching back, lifting the fabric of the thin shirt with it, before grazing her nails back down. Serah squirmed under gentle fingers, pressing her backside further into Lightning. It took the elder Farron the utmost amount of willpower not to ravish the girl on her hands and knees in front of her.

Lightning's lips curled into a smirk.  _She's doing this on purpose._

"You sure you want this? It'll be payback for earlier," Lightning whispered, grasping Serah's ass in her palm.

Serah giggled. "Do your worst,  _Sergeant._ "

Flipping Serah over, Lightning leaned down, marking a fresh trail of kisses down her neck. She grazed her teeth over soft skin as her hand pawed and gripped at a small thigh. Lightning flicked her tongue out to taste, and spoke between kisses under Serah's ear.

"Don't worry, I'll have fun teasing you first."

"Noo _oooo_ , just-  _please…"_ Serah rolled her head to the side, allowing Lightning better access.

Lightning obliged. Kiss after wet kiss, she traveled around Serah's neck, smirking at the moans and whimpers she received under every caress of her lips. A deep chuckle resonated through her. Serah was beyond ready for her – she could practically smell her – but she wouldn't make it that simple. "Please, what? If there's something you want, Serah, just tell me."

"Just- touch me, please?" Serah's hand shot out to grab Lightning's wrist.

Lightning pressed her lips against hers. "Please,  _what?"_

Serah groaned. "Please,  _Sergeant."_

Lightning trailed a finger down the side of Serah's face to the underside of her chin. "Good girl, Serah. Now, where should I touch you, hmm? Show me." With that, Lightning felt her hand being guided up her sister's torso, over a flat belly to the underside of her breasts. "Here?"

Serah nodded.

"Or…" Lightning shifted her hand upwards, her thumb swiping over a hardened nipple. "…here?" She rolled the nipple around between two fingers, gently, watching Serah's reaction.

Serah sucked in a harsh breath, lifting herself to meet more of Lightning's touch. She pulled her bottom lip into her mouth and sucked hard. Serah grabbed the back of Lightning's head, pressing her close to her chest.

A growl rumbled in Lightning's throat as she smiled into Serah's flesh. She chuckled into the sweet skin of her sister, running lips between breasts, and then capturing a hardened bud in her mouth. Running a tongue over the stiff flesh, she busied a hand with the other, repeating movements from before. She peered up at Serah's face; her eyes were squeezed shut, and she chewed on the side of her bottom lip. Cute.

"Claire?" Serah grabbed Lightning's busy hand, stopping it altogether. She moved it, trailing it down her torso, brushing over navel and into her thin shorts.

Lightning smirked. Very forward of her. "Oh? You want me to touch you here?"

Serah nodded.

Her fingers were released, and she took the opportunity to set each hand on either side of the garment. "And what do you want me to do there, Serah?" Her nails raked on the skin there, raising gooseflesh under her fingertips.

"I don't care – lick me, bite me, spank me – just-  _fuck me_." Hips rolled, thighs brushing the sides of Lightning's legs.

Lightning held back her laughter. She grasped Serah's chin, holding her gaze. "I can fuck you, if that's what you want. But you have to be a good kitten and beg first. Will you do that?"

Serah whimpered a quiet "yes."

Releasing her, Lightning backed up, sitting on her heels to look over the girl. Serah gazed up at her with glazed and glassy eyes. Cheeks red, body shaking, and tongue tracing two wonderfully pink lips, Serah was beyond beautiful before her.

Serah pushed herself up onto her knees and crawled towards her elder sister. She tilted her head back to gaze into commanding eyes. Her tongue danced over the lips in front of her. "Sis…please?" She jammed one hand into the front of her shorts. Minor relief only.

With a soft click of teeth, Lightning broke away. "Try harder."

Serah huffed and poked her lips out. She snatched Lightning's arm to yank her backwards onto the bed. She smiled at the startled look on Lightning's face. Using her arm, Serah shoved Lightning over and switched positions. Now between Lightning's legs, she leaned forward to capture the soldier's lips again.

Lightning couldn't help the smug smile that crept across her face. Serah's tickling hands rested on her ribs before traveling upwards. Slow. Labored. Wet lips skimmed across her neck, and in seconds, skilled digits peeled off her beater and bra. Teeth grazed her skin and the jeweled necklace around her collar. Hands fumbled with the studded belt at her waist, pulling and tugging. Lightning sighed. Her nails dragged lightly up the smaller girl's back until she grasped a handful of hair. Serah peered up, smirking, and the two locked eyes.

Serah pressed her face into Lightning's neck and inhaled, running her tongue over skin and vein. She planted a trail of quick pecks from the base of Lightning's neck to just below her ear. A labored moan escaped her. "Pleeease, Lightning?"

Lightning smirked as she felt a hand dip into the front of her jeans. "Maybe." The same hand joined with the other and tugged. Lightning rose, and the jeans were removed, leaving her in blue boyshorts. She cupped Serah's chin, bringing her closer for a kiss.

Serah giggled into Lightning's lips. She pulled away to mark a wet trail down Lightning's neck and torso with her lips, stopping to flick the silver navel stud between her teeth. She halted just above Lightning's underwear and peered up at the soldier.

"If you want something, you better earn it." Lightning raked her hand through silky rose hair and smiled at the purr she received. Of course Serah would be obedient when she wanted a good fuck.

The corner of Serah's mouth rose. She ran a finger across the rim of Lightning's shorts. Dipping her fingers into the waistband, she shimmied them off as Lightning lifted herself.

Lightning shivered, skin marked with gooseflesh from the chilled air. Though she was exposed and vulnerable, being naked in front of her sister was never an issue. They saw one another without clothes often enough, and Guardian Corps. gave her more than enough experience with people in the nude.

Pressing a hand down, Lightning pulled Serah's head closer to core. "Get started, then."

Serah wasted no time. She inhaled, closing her eyes as she took in Lightning's scent. She stretched her body out, lying full out on her stomach before her sister. Her arms clasped around both legs, she pulled Lightning forward. Serah dipped her nose in close before flicking a tongue, giggling at the soldier's sudden flinch.

_That little tease._ A sigh escaped Lightning as she rested her head against the headboard. Her bangs fell over her face, shielding aquamarine eyes. She gasped.

The younger Farron pressed her lips against Lightning's core in a gentle kiss. She took one long stroke, running her tongue from bottom to top, rolling her head under Lightning touch. Her tongue darted around, a quick and even dance in the confines of the soldier's sex.

Lightning all but panted, breaths escaping in short, even gasps. Her palms began to sweat, and she rested the free hand on the bed, grasping a fistful of sheets. Her belly tightened and knotted, body quivering and hips raised in want.

_Shit._

Serah's eyes darted upwards. One, two, three…four strokes of the tongue, and she ended with a kiss. She brushed fingers over Lightning's thigh. Licking her lips, she locked eyes with Lightning, a ghost of a wry smirk playing across her lips.

" _Serah…"_ Lightning hissed. Her grip on the girl's hair tightened. Unacceptable.

Serah grazed Lightning's thigh with her teeth, then nipped a few times. "But, Claire! I need you sooo baaad," she whined, poking her lips out.

She unwrapped one of her arms from Lightning's leg and shoved a hand down her torso, right into her shorts.

Lightning snatched the hand away and proceeded to lace her fingers with Serah's. She spoke, breathing still labored. "No. You… wait your turn. Finish what you started. And clean up when you're done. Understood?"

Serah's thumb rubbed in gentle circles around Lightning's palm. Her eyes turned downwards. "Yes, Sergeant…" She dipped her head back down, capturing Lightning's lower lips in her mouth. Her pacing increased this time.

"That's it…" Lightning's nails raked through silky hair in praise. As sly as Serah was on occasion, she knew just how to work that precious tongue of hers. And damn it all, was it better than anything in the world! Lightning found her teeth gripping her bottom lip hard. Her head scratched against the headboard again. She was so close it hurt.

There was a light chuckle into Lightning's thigh. Serah licked twice, two long strokes, before taking her exposed clit into her mouth and sucking. Lightning squirmed above her. She nipped at a thigh once and then dipped her tongue into Lightning as far as she could, exploring every part.

" _Oh fuuuck…"_ That was it. She couldn't take anymore. Lightning's belly tightened up again, breath growing more ragged. Her hips lifted on instinct, and her entire body shook with delicious delight. She felt a wonderful tingling in every muscle in her body and a searing heat. Toes curling, she squeezed Serah's hand in hers.

_Fucking hell_ , that was brilliant. Her little kitten would have to be rewarded for this.

True to her word, Serah went to work on the wonderful mess between her sister's thighs. She lapped eagerly at the warm stickiness covering each fold. Her tongue gathered up every last bit of the juice in Lightning's center and below. When she was sure she was finished, she gave Lightning a loving kiss on her lower lips. Running her tongue over her own lips, she lifted her head and stared at Lightning. "Claire?"

Lightning attempted to slow her breathing. Two drops of sweat rolled down her face as she sat there staring at her younger sister. With a small smirk, she chuckled and ruffled Serah's hair between her fingers. "Good girl, Serah." Grasping Serah's chin in her hand, she lifted her until Serah closed in herself. She pressed her lips to Serah's mouth, relishing the tangy savor of herself on her lips. "Get ready."

Serah gazed at Lightning expectantly, running a finger up her thigh.

Lightning leaned forward, far enough where Serah moved backwards an inch. In one swift motion, she wrapped an arm around Serah's waist and switched their positions with Serah face up on the bed, Lightning hovering over her. Lightning tugged Serah's thin shirt off immediately. Her eyes roamed over Serah's bare torso, taking in every familiar and beautiful curve. Her lips curled upwards at Serah's smirking form below her. "What are you smiling at?"

"Haha, nothing! I-  _ah,_ Lightning!"Serah rolled her hips at the teasing finger on the outside of her shorts. " _Mmm,_ I love it when you get like this."

"I love it when you say my name. Maybe I can make you scream it." Lightning ran her tongue over her lip. She tugged at Serah's waistband. "Off."

Serah obeyed. She never broke eye contact with her sister as she lifted her hips and slid her shorts down slender legs.

Lightning raised an eyebrow and licked her lips at the sight before her. Serah wore nothing but a simple black pair of panties adorned with a single bolt of white lightning down the center.

"You changed?"

Serah's face flushed bright red. "Earlier, yeah. Your favorite."

"They are. But…" Lightning lowered herself to Serah's ear. "Don't want to ruin them, now, do we?"

" _Mmm_ , no…"

"Right. So take them off."

Serah wrapped an arm around Lightning's neck, pulling her closer. "I like it better when youdo it."

The elder Farron couldn't help but smile. Gods, this girl had Lightning wrapped around her finger. No excuses; Lightning would give Serah what she earned. She planted a quick peck on her sister's ear and lowered herself. Lightning kissed a trail down Serah's abdomen, brushing past her navel and stopping before her sister's panties.

"Up."

Serah watched intently as she lifted her hips just off the bed.

Grazing her teeth over heated skin, she nipped and bit at the flesh below Serah's navel. She grasped the fabric between her teeth and pulled until she rid her sister of it. Throwing the underwear to the floor, Lightning looked back up at Serah. She was absolutely gorgeous, so naked and wanting. Lightning's heart fluttered in her chest. She considered herself lucky to have such a strong, beautiful, intelligent woman for a sister. Serah was perfect.

"Claire?"

Lightning snapped out of her thoughts and focused. She ran her tongue across the inside of Serah's thigh, eliciting a moan. She chuckled.

Serah raked fingers through Lightning's messy mane. "Stop laughing."

"Stop being so adorable." Lightning raised a leg up, running her tongue up to the knee.

" _Aahh…_  can't help it. S-special talent of mine," Serah groaned.

Lightning laughed into Serah's skin. She kissed a line up her sister's leg as Serah all but squirmed underneath. Stopping at the apex of Serah's thighs, Lightning leaned in close, breathing against the sensitive skin. She wasted no time, running her tongue up the length of Serah's opening. Serah expelled a shallow gasp past her lips.

Serah rolled her hips under Lightning's tongue. "Oohh, god,  _please…_ "

A sly smirk crept upon Lightning's face. "I haven't even started yet." She lifted her hand to caress Serah's cheek, and then cupped her chin. She moved her fingers in front of Serah and felt the wetness of her mouth capturing two of them.

Sighing, Serah licked and caressed every inch of the two digits in her mouth. Grabbing Lightning's wrist, she sucked on the fingers eagerly, a small bit of saliva dripping down her chin. She locked eyes with Lightning, a lustful gaze beneath a half-lidded, submissive stare.

Lightning yanked her fingers from Serah's mouth. She rose and leaned in to brush against her sister's sweet lips, but her eyes widened at Serah's vice grip on her hair.

Serah traced the outside of Lightning's ear with her lips, closing her eyes to whisper. "Fuck me."

Nose close to Serah's neck, she inhaled, the wonderful flowery aroma masked by the smell of sweat and lust. Her wet fingers hovered over Serah's opening, teasing, tracing sickeningly taunting circles. Finally, she pushed. It was slow, slack in progress, but slick to the touch. Serah was beyond wet.

"Anything…" She pushed further, only one finger in to the knuckle. "Anything, for my little princess."

The younger Farron's eyes shut in an instant. Raking and scratching through Lightning's hair, she threw her head to the side, furrowing her brows. Her free hand trailed up her midsection, stopping to tweak and twist at her nipples.

The corner of Lightning's lip rose. "Been a while, huh?" Serah whimpered and nodded below her. Of course it had. Lightning planted a chaste kiss on Serah's neck before lowering herself to her belly. Finger moving slowly, she flicked her tongue out over the girl's clit, only to capture it between her lips. Serah shook once and lifted her hips an inch off the mattress, but Lightning pushed her back down with a free hand on her abdomen. Lightning drove her tongue in beside the finger, jerking it about. Pulling back for a second, she licked her lips and looked up at Serah, grinning.

Serah slammed Lightning's head back between her legs, rolling her head around on the pillow.

Lightning chuckled into Serah's thigh. Nipping once at the sensitive skin, she hovered a second teasing finger near Serah's opening, then a third. With one final lick, she pushed the second finger in with care, noting the heavy sigh escaping from her beloved sister. Just one more. As with the second, the third finger entered Serah, slow enough to allow her to grow accustomed to the stretch.

The breath that escaped Serah then was akin to a squeak. She threaded her fingers through the soldier's hair once, and grasped her bottom lip between her teeth.

Fuck. It  _had_  been too long, Lightning admitted. Months, actually. Serah must have waited the entire time until she had a chance to release all her pent-up frustrations, which would have explained her friskier-than-usual behavior today. Even then, she was still as tight as ever as Lightning's fingers continued to push further into her.  _Almost there._

Serah breathed a sigh of relief. She was filled to the brim, spreading her legs a little wider.

With that, Lightning started a slow rhythm, pumping her fingers in and out of Serah's slit. She lowered herself once more and inhaled the deep, heady scent of the younger Farron. Fucking hell. She drew Serah closer with her arm wrapped around Serah's leg, driving her tongue out. With sporadic laps of the tongue, Lightning curled her fingers inside of Serah.

"Oh, my  _gooood…"_  Serah bucked her hips into Lightning's busy mouth. Her fingers danced through a wild, strawberry-blond mane while her back arched off the bed.

And in a second, Lightning stopped. She rose and looked down over her lust-ridden sister, fingers still buried within.

Serah wasted no time in clasping her arms around Lightning's neck, aiming to whisper in her ear but coming up with a moan instead. Before she could utter a word, Lightning pulled her forward, wrapping an arm around her bare midsection. Serah instinctively coiled her legs around the sergeant's waist.

Lightning lifted Serah with ease and leaned back, sitting on the bed with Serah in her lap. She slammed her fingers into that  _one spot_  that graced her with delicious squeaks and moans in her ear. Serah's breasts glided across her own, a thin layer of sweat joining the two. Lightning ran her nose and lips up the length of Serah's neck, then dragged her teeth back down. Heavens, Serah smelled so good when she was aroused, Lightning contemplated on continuing to ravage her with just her lips and tongue.

She latched onto a spot, one just under the left side of Serah's jaw. Nipping and sucking, Serah squirmed on top of her. Lightning found Serah easily matching her rough and steady rhythm, Serah's hips moving in slow, deep circles, catching every thrust into her.

She sucked in a breath at the lips claiming her neck and- "Oh,  _Etro_. Mmm… Lightning…"

Oh? Name calling already? Lightning chuckled into Serah's neck, feeling a shiver jolt through the younger girl's hot and sweaty body. "Say it again."

"Unnhh,  _Lightniiiing…"_  Serah dropped herself harder, faster.

"Again. Louder."

Harder,  _harder._

"Lightning-  _fuck, Claaiiire_! Oh, god…" Serah tightened her grip around Lightning's neck.

Lightning rubbed that sweet spot with her fingers before driving into it again. She didn't know the next time they'd be able to spend so much time together; she had to make it count. Serah all but bounced in her lap now, meeting her thrusts with perfect timing. Lightning held her close, letting Serah's lean belly brush against her own toned abs. Grazing her teeth against Serah's neck once more, she whispered into the girl's skin.

"Whose are you?"

She buried her face into the soldier's neck and gasped.

"Yours."

Lightning thrust twice, hard, causing Serah to shake. "I didn't quite hear you."

Whimpering, Serah planted her lips on Lightning's neck, slamming herself harder into Lightning's fingers. "Yours. Mmm _…_ I'm yo-  _ahhh!"_

" _Serah_."

Serah moaned between heavy thrusts. "Yours! I'm yours, Claire-  _oh fuck,_ I'm- yours!"

Serah's body trembled on top of her sister. Lightning could feel the life being squeezed out of her fingers as Serah came on top of her. The motion in her lap slowed down to a halt, heavy breaths ghosting her ear. The arms around her neck loosened and Serah's body slumped against her own.

Lightning's fingers traveled down her sister's spine in tender caresses. "You're all mine, right? No one else's?"

The younger Farron's voice came out in a lazy drawl. "Uh uh. No one else's. Just yours. All yours _,_  Claire."

Carefully, Lightning pulled her soaked fingers out of Serah's center. She cleaned them off with her tongue, savoring the sweet-tangy flavor of her beloved sister. With both hands free, she laid Serah down on the bed. Her eyes roved over the nearly sleeping girl. She smiled to herself, lucky to have such a beautiful and passionate sister. She caressed Serah's cheek with her knuckles, then stopped. She had to work tomorrow, she recalled. Swearing under her breath, she crawled up next to Serah to lay at her side.

Serah scooted closer, face buried in Lightning's bare chest. She grabbed Lightning's arm, throwing it over herself, cuddling closer into her soldier. "Take off work tomorrow. Please?"

Lightning leaned in, capturing Serah's lips in a slow dance of lips and tongue. "I can't. It's too late. I'm sorry."

"Okay. I'll miss you." Serah rested her forehead against Lightning's neck and fingered the jeweled necklace around her neck.

"What if I take off next weekend?"

"Serah?" Lightning narrowed her eyes. Shallow even breaths reached her ears, followed by a long sigh.

_She's asleep._

Lightning smiled, kissing the top of Serah's head. She pulled her sister closer in her protective hold and drifted to sleep.


	4. Epilogue

**Summary for the Chapter:**

> Lightning finally has a day off to spend time with her sister, Serah. Lightning knows Serah - she isn't as innocent as everyone thinks she is - but yet the soldier still can't resist her. Farroncest. Written for FFXIII Kink Meme.

**Notes for the Chapter:**

> Title: Bonding - Epilogue  
> Pairing: Farroncest (Lightning/Serah)  
> Rating: M for sisterly incest, language, very mild breath play  
> Words: 1,944  
> Song Inspiration: None  
> Prompt Request: "Lightning may dominate Serah in bed, but sex-devious Serah is the one who really pulls the strings in their relationship. Orrrrr simply, Lightning can't resist Serah, and Serah ALWAYS gets what she wants from big sis."
> 
> A/N: I told myself I wasn't coming back to this fic, and yet, here I am. Okay, this is the absolute last chapter of the fic. I won't be updating this anymore. It's a short smut scene. I hope you like it and thanks to everyone who's stuck around reading this for the last two years. I really do appreciate it. Please enjoy the final, short part of Bonding!  
> \- Also, if you aren't following me on tumblr already, I do occasionally post small ficlets there that I don't upload anywhere else. So if you're interested in those, you can find me on tumblr at @fyeahnix

"Just leave it."

"It's Amodar. I can't- mmf…"

"Wha's wrong? Cat got your tongue?"

" _Serah."_

Lightning didn't have to see well to know that there was a mischievous smirk plastered on her sister's face. Before she considered kissing her back, she snatched the vibrating phone from the night stand as Serah drifted over her and off the bed. Sure enough, the Lieutenant's name flashed across the screen.

"Hello?"

"Ah, Lightning. Thought you wouldn't pick up for a second. Listen, I know it's early…"

Serah returned seconds later, resting her head on Lightning's shoulder. "What's up?" she whispered.

Lightning gave her a quick "nothing yet" before returning the phone to her ear. Serah turned and shifted to rest her chin between the soldier's breasts.

"…have a lot of work to do, and it seems like PSICOM may be stepping in to help us…"

"Right."

Despite the darkness of the bedroom, Lightning made out Serah's scrunched eyebrows and poked out lip. Amodar's long-winded droning buzzed on in her ear, and since it wasn't even four in the morning yet, she found herself agreeing with Serah's confused pout. The Lieutenant had a nasty habit of disclosing information irrelevant to the issue at hand. Still, he was her superior, and despite her half-listening to his too-enthusiastic-for-the-morning tirade, it was only right to throw in an acknowledgement every few sentences or so.

Serah seemed to take it all in stride, but her annoyance was evident. Nimble fingers traced at Lightning's sides, making her quiver under Serah's weight with the rise of gooseflesh. There was the occasional roll of the eyes, a quick nip at the skin between Lightning's breasts, and, yes, of course, a playful moan right outside the shell of Lightning's unused ear. Comical, sure, but uncalled for. Serah was playing dirty.

At long last, it seemed that Amodar had finished his explanation, and the sergeant breathed a sigh of relief.

"Long story short, you can take the day off. Let your squad know, and I'll see you all bright and early tomorrow."

"I see. Yes, sir, I will."

"Get some rest, Lightning."

As the Lieutenant hung up, Serah brushed her nose into Lightning's neck. "You're off?"

A single breath of air whispered from Lightning's lungs as Serah's fingers tickled the underside of her breast. "Apparently so." Lightning's own fingers ghosted down Serah's spine, eliciting the smallest of shudders from the younger Farron. "I need to let my squad know."

" _Claaaiire_ , it's three in the morning. They can wait." Serah's teeth nipped her, just hard enough to coax a rumble from the soldier's throat. "I can't."

The hand on Serah's back marked shape after lazy shape as Lightning formulated the text with her other hand. A simple "no work today" would suffice; it was early as Serah mentioned. Swiping the screen proved difficult with the soft sighs tickling her neck, but Serah was at least nice enough to stay still for more than ten seconds.

Before Lightning locked the phone, Serah snatched it from her and placed it on the nightstand. "Back to me."

"You know you're more important, Serah," Lightning growled, running a hand down to cup Serah's ass.

Bucking into the hand on her backside, Serah grasped at the sheets next to Lightning, expelling a shaky breath into Lightning's neck. "Am I, Claire? Why don't you show me?"

Lightning's brows furrowed, and her gentle caress ceased. "Serah, again?" Not that she was overly surprised, but they'd gone at it, what, four or five times that day? "Don't you need a break? Aren't you tired?"

With a passionate kiss to Lightning's lips, Serah pushed herself off Lightning, moving to situate herself over one leg. "I am. Make me go to sleep."

" _Serah_ -"

The younger Farron ground against Lightning's thigh, most likely aiming to cut her off. Of course, it worked, as Lightning thought of nothing but the slick wetness sliding on her leg. Etro, why did it always come to this? She never could resist Serah's needs.

Serah released a deep-seated growl from the pit of her being. With one hand, she trailed careful fingers down Lightning's neck, breasts, and abdomen, dragging herself along Lightning's leg. Her hand returned to Lightning's neck, and nimble fingers pressed into the skin.

Lightning swallowed hard, feeling her airway constrict under Serah's hand. She bit her lip, clearing her throat before she spoke."Fine. Need some help?"

Serah's pace became oddly timed, mixing short and long thrusts at random intervals. She lost herself in her own rhythm, mumbling to herself about Etro knows what. It took her about ten seconds – Lightning counted – before Serah graced the soldier with a response.

"Uhh… maybe. I dunno. I jus' really wish you could see me right now. Don't you wanna watch?" Serah's grip on Lightning's neck disappeared.

Lightning inhaled a sharp breath as stars flickered in front of her eyes. Those words struck a chord with her as Serah knew just how much Lightning got off to watching her pleasure herself. Serah's words came out slurred too, so she was already lost in her own little hazy world. Lightning reached out, fumbling about the bed for her phone, and then tried the nightstand. Phone in hand, she took in a breath before unlocking it and shining the light on Serah.

Serah must have noticed the light behind her shut eyes, because she made sure she bit her bottom lip and forced out the sexiest fucking moan Lightning's ever heard. Sweat beaded on her forehead, and hair clung to her skin like a magnet. Her breasts bounced, and Lightning found herself reaching up to cup one in her hand, brushing her thumb over the nipple. Serah flashed a teasing smirk at her.

"That… feels really good," Serah sighed, her nails raking down Lightning's abdomen. "But, how's the view?"

Lightning's eyes began to wander at Serah's words. The view was, for lack of a better word, magnificent. Serah's hips gyrated, grinding her heated core against Lightning's thigh. Lightning found herself mesmerized at the expression of sheer lust on Serah's face. Her eyes remained closed, her lips parted, and her head tilted back a few degrees. The phone clicked off, causing Lightning to growl in frustration. Serah chuckled at her as she unlocked the phone once more, dragging the light further down Serah's body. Not a day went by that Lightning didn't find herself marveling over Serah. The girl was petite, sure, but she still had soft curves in all the right places. Lightning, in contrast, sported sharp, angular features and a body seemingly cut out of marble.

Lightning chuckled as she glanced down, watching Serah's hand furl and unfurl at Lightning's belly. "Perfect." The hand on Serah's breast teased and flicked at Serah's nipple.

"Oh… oh yeah? What do you like to see?"

Everything, really. But Serah was trying to tease her, and Lightning enjoyed the effort. Lightning removed her hand from Serah's breast and gave her a swift smack on the ass. Serah swore under her breath, grabbing Lightning's hand and intertwining their fingers. She stopped her pace, probably to prevent herself from driving over the edge so soon. The wetness of Serah's core on Lightning's thigh became more noticeable, and Lightning uttered a heated swear under her breath.

Lightning adjusted the phone's light before she spoke. "All of you. You're beautiful, Serah. You know that."

The smaller girl hummed to herself. "I know. But, ugh, you're so bad at dirty talk this early in the morning."

"You're the one who wanted to fuck at this hour."

Serah huffed. "Okay, but, like. Play along at least? You killed my high, so you better help me come."

A soft chuckle escaped Lightning, one that morphed into a sharp moan at Serah's fingers dancing around her entrance. "Ah… you're such a little minx, you know that?"

"I'm aware. I'm also your sister, your princess, and-" Serah lowered herself to Lightning's ear, grazing the shell with her tongue. "-your little kitten, right?"

"Right," Lightning whispered through gritting teeth.

"So make me purr and watch me come for you."

That just about did it for Lightning. Serah sat back up and started slow grinding on her leg again, throwing her head back. Lightning swallowed a hard lump in her throat, keeping her eyes on the rolling hips before her. One hand crept forward, brushing hair and thumbing Serah's clit. A rough shudder coursed through the girl before she let go of Lightning's other hand to cup and caress her breasts.

Lightning set the phone down at her side, allowing the flash to remain on. Though seeing Serah wasn't a necessity, Lightning was glad she could still make out every part of her. And quite frankly, Serah was beyond sexy as hell rolling her hips like that.  _Fuck_.

"Mmm… Gonna borrow your hand, okay?"

Lightning slid her thumb further down Serah's clit, causing the girl to hiss. "So you're just gonna use me to fuck yourself?"

"Shhhhut up. You like it."

Lightning chuckled, setting her free hand on Serah's hip. She rocked the girl on top of her, grinding Serah against the hand at her clit. Serah jerked her hips more forcefully. She pinched at her nipples, tweaking them under Lightning's watchful gaze. Lightning refused to take her eyes off Serah; if Serah wanted her to watch, then she damn well would.

Serah adjusted Lightning's hand before a guttural groan ripped from her chest. Lightning watched Serah as she fell forward, heavy panting and hot breaths tickling her ear. Lightning waited. Maybe there was some sign Serah would give her about what she wanted to do next; there usually was. But with the shudder that jolted through her sister, she remained unsure. Lightning removed the hand from Serah's hip to cup the back of her neck and run it through the strands of her hair.

Serah pressed her face into Lightning's neck. She attempted to force words out, Lightning picked up, but they emerged in choppy syllables, strained sounds mixed between moaning and crying.

"I'm… I'm gonna come. I'm gonna come so hard,  _Claire_."

Lightning grinned. The grinding became more vigorous. Slick squelching of arousal against her leg blended in with the slight squeaking of the bed frame. Serah's moans added to the mix, creating a sweet symphony of sound Lightning admitted lit her insides on fire.

Teeth sank into Lightning's neck. A shudder rocked her body as Serah's moans were lost, muffled and drowned out into her collarbone. Serah came hard, orgasm ripping through every fiber of her being as she trembled on top of Lightning. A jumbled mess of words expelled from Serah. She spoke confidently, as if every syllable made perfect sense in that muddled head of hers. Lightning couldn't understand her, and instead of encouraging Serah to continue, she removed her arousal-slick hand from under Serah's clit to clean her fingers.

It took Lightning several tries, if one wanted to call bribing kisses 'tries,' before Serah rolled off Lightning's thigh of her own accord, and Lightning shut the phone off. Serah lay at her side, snuggled up into Lightning's chest and neck as she dozed. Lightning chose to ignore the musky wetness atop her thigh; they'll shower first thing in the morning, and she was already beyond tired.

Despite the limited time they've had to spend with one another, Lightning cherished every second she had with Serah over the course of the day. With any luck, it'll be just as eventful with her extra day off. Everything about Serah – her laugh, her touches, her kisses,  _their bond_  – made every single endeavor Lightning endured worth it.

And to be honest, she wouldn't have had it any other way.


End file.
